diff --git a/demos/modules/gadc/gwinosc.c b/demos/modules/gadc/gwinosc.c
index 193957ee..60dc1798 100644
--- a/demos/modules/gadc/gwinosc.c
+++ b/demos/modules/gadc/gwinosc.c
@@ -36,10 +36,7 @@
 #include "gwinosc.h"
 
 /* Include internal GWIN routines so we can build our own superset class */
-#include "gwin/internal.h"
-
-/* Our GWIN identifier */
-#define GW_SCOPE				(GW_FIRST_USER_WINDOW+0)
+#include "gwin/class_gwin.h"
 
 /* The size of our dynamically allocated audio buffer */
 #define AUDIOBUFSZ				64*2
@@ -47,23 +44,40 @@
 /* How many flat-line sample before we trigger */
 #define FLATLINE_SAMPLES		8
 
-GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coord_t cy, uint32_t physdev, uint32_t frequency) {
-	/* Initialise the base class GWIN */
-	if (!(gs = (GScopeObject *)_gwinInit((GWindowObject *)gs, x, y, cx, cy, sizeof(GScopeObject))))
-		return 0;
+static void _destroy(GHandle gh) {
+	gadcHighSpeedStop();
+	if (((GScopeObject *)gh)->lastscopetrace) {
+		gfxFree(((GScopeObject *)gh)->lastscopetrace);
+		((GScopeObject *)gh)->lastscopetrace = 0;
+	}
+	if (((GScopeObject *)gh)->audiobuf) {
+		gfxFree(((GScopeObject *)gh)->audiobuf);
+		((GScopeObject *)gh)->audiobuf = 0;
+	}
+}
 
-	/* Initialise the scope object members and allocate memory for buffers */
-	gs->gwin.type = GW_SCOPE;
+static const gwinVMT scopeVMT = {
+		"Scope",				// The classname
+		sizeof(GScopeObject),	// The object size
+		_destroy,				// The destroy routine
+		0,						// The redraw routine
+		0,						// The after-clear routine
+};
+
+GHandle gwinScopeCreate(GScopeObject *gs, GWindowInit *pInit, uint32_t physdev, uint32_t frequency) {
+	/* Initialise the base class GWIN */
+	if (!(gs = (GScopeObject *)_gwindowCreate(&gs->g, pInit, &scopeVMT, 0)))
+		return 0;
 	gfxSemInit(&gs->bsem, 0, 1);
 	gs->nextx = 0;
-	if (!(gs->lastscopetrace = (coord_t *)gfxAlloc(gs->gwin.width * sizeof(coord_t))))
+	if (!(gs->lastscopetrace = (coord_t *)gfxAlloc(gs->g.width * sizeof(coord_t))))
 		return 0;
 	if (!(gs->audiobuf = (adcsample_t *)gfxAlloc(AUDIOBUFSZ * sizeof(adcsample_t))))
 		return 0;
 #if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
-	gs->lasty = gs->gwin.height/2;
+	gs->lasty = gs->g.height/2;
 #elif TRIGGER_METHOD == TRIGGER_MINVALUE
-	gs->lasty = gs->gwin.height/2;
+	gs->lasty = gs->g.height/2;
 	gs->scopemin = 0;
 #endif
 
@@ -72,10 +86,11 @@ GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coor
 	gadcHighSpeedSetBSem(&gs->bsem, &gs->myEvent);
 	gadcHighSpeedStart();
 
+	gwinSetVisible((GHandle)gs, pInit->show);
 	return (GHandle)gs;
 }
 
-void gwinWaitForScopeTrace(GHandle gh) {
+void gwinScopeWaitForTrace(GHandle gh) {
 	#define 		gs	((GScopeObject *)(gh))
 	int				i;
 	coord_t			x, y;
@@ -91,6 +106,9 @@ void gwinWaitForScopeTrace(GHandle gh) {
 	coord_t			scopemin;
 #endif
 
+	if (gh->vmt != &scopeVMT)
+		return;
+
 	/* Wait for a set of audio conversions */
 	gfxSemWait(&gs->bsem, TIME_INFINITE);
 
diff --git a/demos/modules/gadc/gwinosc.h b/demos/modules/gadc/gwinosc.h
index 406caec2..ecf5108c 100644
--- a/demos/modules/gadc/gwinosc.h
+++ b/demos/modules/gadc/gwinosc.h
@@ -56,7 +56,7 @@
 
 /* A scope window object. Treat it as a black box */
 typedef struct GScopeObject_t {
-	GWindowObject		gwin;					// Base Class
+	GWindowObject		g;						// Base Class
 
 	coord_t				*lastscopetrace;		// To store last scope trace
 	gfxSem				bsem;					// We get signalled on this
@@ -78,18 +78,12 @@ extern "C" {
 	/**
 	 * Create a scope window.
 	 */
-	GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coord_t cy, uint32_t physdev, uint32_t frequency);
+	GHandle gwinScopeCreate(GScopeObject *gs, GWindowInit *pInit, uint32_t physdev, uint32_t frequency);
 
 	/**
 	 * Wait for a scope trace to be ready and then draw it.
 	 */
-	void gwinWaitForScopeTrace(GHandle gh);
-
-	/**
-	 * We should also have a special destroy routine here as we have dynamically
-	 * allocated some memory. There is no point implementing this however as, for
-	 * this demo, we never destroy the window.
-	 */
+	void gwinScopeWaitForTrace(GHandle gh);
 
 #ifdef __cplusplus
 }
diff --git a/demos/modules/gadc/main.c b/demos/modules/gadc/main.c
index 6cf30023..928635fa 100644
--- a/demos/modules/gadc/main.c
+++ b/demos/modules/gadc/main.c
@@ -37,7 +37,6 @@
  * It also demonstrates how to write your own custom GWIN window type.
  */
 #include "gfx.h"
-#include "chprintf.h"
 
 /* Include our custom gwin oscilloscope */
 #include "gwinosc.h"
@@ -82,7 +81,7 @@ static GTimer				lsTimer;
 				|| (lastdial > dialvalue && lastdial - dialvalue > MY_DIAL_JITTER)) {
 
 			/* Write the value */
-			chprintf((BaseSequentialStream *)param, "DIAL: %u\n", dialvalue);
+			gwinPrintf((GHandle)param, "DIAL: %u\n", dialvalue);
 
 			/* Save for next time */
 			lastdial = dialvalue;
@@ -107,7 +106,7 @@ static GTimer				lsTimer;
 				|| (lasttemp > tempvalue && lasttemp - tempvalue > MY_TEMP_JITTER)) {
 
 			/* Write the value */
-			chprintf((BaseSequentialStream *)param, "TEMP: %u\n", tempvalue);
+			gwinPrintf((GHandle)param, "TEMP: %u\n", tempvalue);
 
 			/* Save for next time */
 			lasttemp = tempvalue;
@@ -138,7 +137,6 @@ int main(void) {
 	coord_t					swidth, sheight;
 	#if defined(MY_DIAL_DEVICE) || defined(MY_TEMP_DEVICE)
 		GHandle					ghText;
-		BaseSequentialStream	*gsText;
 		font_t					font;
 	#endif
 
@@ -151,19 +149,34 @@ int main(void) {
 	#if defined(MY_DIAL_DEVICE) || defined(MY_TEMP_DEVICE)
 		/* Set up the console window we use for dial readings */
 		font = gdispOpenFont("UI2");
-		ghText = gwinCreateConsole(&gTextWindow, 0, 0, swidth-SCOPE_CX, sheight, font);
+		gwinSetDefaultFont(font);
+		{
+			GWindowInit	wi;
+			wi.show = TRUE;
+			wi.x = wi.y = 0;
+			wi.width = swidth-SCOPE_CX;
+			wi.height = sheight;
+			ghText = gwinConsoleCreate(&gTextWindow, &wi);
+		}
 		gwinSetBgColor(ghText, Black);
 		gwinSetColor(ghText, Yellow);
 		gwinClear(ghText);
-		gsText = gwinGetConsoleStream(ghText);
 
 		/* Start our timer for reading the dial */
 		gtimerInit(&lsTimer);
-		gtimerStart(&lsTimer, LowSpeedTimer, gsText, TRUE, MY_LS_DELAY);
+		gtimerStart(&lsTimer, LowSpeedTimer, ghText, TRUE, MY_LS_DELAY);
 	#endif
 
 	/* Set up the scope window in the top right on the screen */
-	ghScope = gwinCreateScope(&gScopeWindow, swidth-SCOPE_CX, 0, SCOPE_CX, SCOPE_CY, MY_MIC_DEVICE, MY_MIC_FREQUENCY);
+	{
+		GWindowInit	wi;
+		wi.show = TRUE;
+		wi.x = swidth-SCOPE_CX;
+		wi.y = 0;
+		wi.width = SCOPE_CX;
+		wi.height = SCOPE_CY;
+		ghScope = gwinScopeCreate(&gScopeWindow, &wi, MY_MIC_DEVICE, MY_MIC_FREQUENCY);
+	}
 	gwinSetBgColor(ghScope, White);
 	gwinSetColor(ghScope, Red);
 	gwinClear(ghScope);
@@ -174,6 +187,6 @@ int main(void) {
 		 * The function below internally performs a wait thus giving the timer thread a
 		 * chance to run.
 		 */
-		gwinWaitForScopeTrace(ghScope);
+		gwinScopeWaitForTrace(ghScope);
 	}
 }
diff --git a/demos/modules/gaudin/gwinosc.c b/demos/modules/gaudin/gwinosc.c
index d90742ee..9882bcde 100644
--- a/demos/modules/gaudin/gwinosc.c
+++ b/demos/modules/gaudin/gwinosc.c
@@ -43,10 +43,7 @@
 #include "gwinosc.h"
 
 /* Include internal GWIN routines so we can build our own superset class */
-#include "gwin/internal.h"
-
-/* Our GWIN identifier */
-#define GW_SCOPE				(GW_FIRST_USER_WINDOW+0)
+#include "gwin/class_gwin.h"
 
 /* The size of our dynamically allocated audio buffer */
 #define AUDIOBUFSZ				64*2
@@ -54,23 +51,42 @@
 /* How many flat-line sample before we trigger */
 #define FLATLINE_SAMPLES		8
 
-GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coord_t cy, uint16_t channel, uint32_t frequency) {
+static void _destroy(GHandle gh) {
+	gaudinStop();
+	if (((GScopeObject *)gh)->lastscopetrace) {
+		gfxFree(((GScopeObject *)gh)->lastscopetrace);
+		((GScopeObject *)gh)->lastscopetrace = 0;
+	}
+	if (((GScopeObject *)gh)->audiobuf) {
+		gfxFree(((GScopeObject *)gh)->audiobuf);
+		((GScopeObject *)gh)->audiobuf = 0;
+	}
+}
+
+static const gwinVMT scopeVMT = {
+		"Scope",				// The classname
+		sizeof(GScopeObject),	// The object size
+		_destroy,				// The destroy routine
+		0,						// The redraw routine
+		0,						// The after-clear routine
+};
+
+GHandle gwinScopeCreate(GScopeObject *gs, GWindowInit *pInit, uint16_t channel, uint32_t frequency) {
 	/* Initialise the base class GWIN */
-	if (!(gs = (GScopeObject *)_gwinInit((GWindowObject *)gs, x, y, cx, cy, sizeof(GScopeObject))))
+	if (!(gs = (GScopeObject *)_gwindowCreate(&gs->g, pInit, &scopeVMT, 0)))
 		return 0;
 
 	/* Initialise the scope object members and allocate memory for buffers */
-	gs->gwin.type = GW_SCOPE;
 	gfxSemInit(&gs->bsem, 0, 1);
 	gs->nextx = 0;
-	if (!(gs->lastscopetrace = (coord_t *)gfxAlloc(NULL, gs->gwin.width * sizeof(coord_t))))
+	if (!(gs->lastscopetrace = (coord_t *)gfxAlloc(gs->g.width * sizeof(coord_t))))
 		return 0;
-	if (!(gs->audiobuf = (adcsample_t *)gfxAlloc(NULL, AUDIOBUFSZ * sizeof(adcsample_t))))
+	if (!(gs->audiobuf = (adcsample_t *)gfxAlloc(AUDIOBUFSZ * sizeof(adcsample_t))))
 		return 0;
 #if TRIGGER_METHOD == TRIGGER_POSITIVERAMP
-	gs->lasty = gs->gwin.height/2;
+	gs->lasty = gs->g.height/2;
 #elif TRIGGER_METHOD == TRIGGER_MINVALUE
-	gs->lasty = gs->gwin.height/2;
+	gs->lasty = gs->g.height/2;
 	gs->scopemin = 0;
 #endif
 
@@ -79,10 +95,11 @@ GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coor
 	gaudinSetBSem(&gs->bsem, &gs->myEvent);
 	gaudinStart();
 
+	gwinSetVisible((GHandle)gs, pInit->show);
 	return (GHandle)gs;
 }
 
-void gwinWaitForScopeTrace(GHandle gh) {
+void gwinScopeWaitForTrace(GHandle gh) {
 	#define 		gs	((GScopeObject *)(gh))
 	int				i;
 	coord_t			x, y;
@@ -98,6 +115,9 @@ void gwinWaitForScopeTrace(GHandle gh) {
 	coord_t			scopemin;
 #endif
 
+	if (gh->vmt != &scopeVMT)
+		return;
+
 	/* Wait for a set of audio conversions */
 	gfxSemWait(&gs->bsem, TIME_INFINITE);
 
diff --git a/demos/modules/gaudin/gwinosc.h b/demos/modules/gaudin/gwinosc.h
index ff13a060..6a559c34 100644
--- a/demos/modules/gaudin/gwinosc.h
+++ b/demos/modules/gaudin/gwinosc.h
@@ -62,7 +62,7 @@
 
 /* A scope window object. Treat it as a black box */
 typedef struct GScopeObject_t {
-	GWindowObject		gwin;					// Base Class
+	GWindowObject		g;						// Base Class
 
 	coord_t				*lastscopetrace;		// To store last scope trace
 	gfxSem				bsem;					// We get signalled on this
@@ -84,18 +84,12 @@ extern "C" {
 	/**
 	 * Create a scope window.
 	 */
-	GHandle gwinCreateScope(GScopeObject *gs, coord_t x, coord_t y, coord_t cx, coord_t cy, uint16_t channel, uint32_t frequency);
+	GHandle gwinScopeCreate(GScopeObject *gs, GWindowInit *pInit, uint16_t channel, uint32_t frequency);
 
 	/**
 	 * Wait for a scope trace to be ready and then draw it.
 	 */
-	void gwinWaitForScopeTrace(GHandle gh);
-
-	/**
-	 * We should also have a special destroy routine here as we have dynamically
-	 * allocated some memory. There is no point implementing this however as, for
-	 * this demo, we never destroy the window.
-	 */
+	void gwinScopeWaitForTrace(GHandle gh);
 
 #ifdef __cplusplus
 }
diff --git a/demos/modules/gaudin/main.c b/demos/modules/gaudin/main.c
index 2f3759ff..32418450 100644
--- a/demos/modules/gaudin/main.c
+++ b/demos/modules/gaudin/main.c
@@ -59,13 +59,20 @@ int main(void) {
 	sheight = gdispGetHeight();
 
 	/* Set up the scope window to fill the screen */
-	ghScope = gwinCreateScope(&gScopeWindow, 0, 0, swidth, sheight, MY_AUDIO_CHANNEL, MY_AUDIO_FREQUENCY);
+	{
+		GWindowInit	wi;
+
+		wi.show = TRUE;
+		wi.x = wi.y = 0;
+		wi.width = swidth; wi.height = sheight;
+		ghScope = gwinScopeCreate(&gScopeWindow, &wi, MY_AUDIO_CHANNEL, MY_AUDIO_FREQUENCY);
+	}
 	gwinSetBgColor(ghScope, White);
 	gwinSetColor(ghScope, Red);
 	gwinClear(ghScope);
 
 	/* Just keep displaying the scope traces */
 	while (TRUE) {
-		gwinWaitForScopeTrace(ghScope);
+		gwinScopeWaitForTrace(ghScope);
 	}
 }