diff --git a/windows/datetimepicker.cpp b/windows/datetimepicker.cpp
index b81cfe6f..4f9a00fa 100644
--- a/windows/datetimepicker.cpp
+++ b/windows/datetimepicker.cpp
@@ -44,7 +44,7 @@ static WCHAR *expandYear(WCHAR *dts, int n)
 				if (*p == L'\'')
 					break;
 				if (*p == L'\0')
-					complain("unterminated quote in system-provided locale date string in expandYear()");
+					implbug("unterminated quote in system-provided locale date string in expandYear()");
 				*q++ = *p;
 			}
 			// and fall through to copy the closing quote
diff --git a/windows/debug.cpp b/windows/debug.cpp
index 0b0d1e03..7af79e69 100644
--- a/windows/debug.cpp
+++ b/windows/debug.cpp
@@ -71,10 +71,10 @@ void realbug(const char *file, const char *line, const char *func, const char *p
 	va_copy(ap2, ap);
 	n = _vscprintf(format, ap2);
 	va_end(ap2);
-	n++;		// terminating L'\0'
+	n++;		// terminating '\0'
 
 	buf = (char *) uiAlloc(n * sizeof (char), "char[]");
-	// includes terminating L'\0' according to example in https://msdn.microsoft.com/en-us/library/xa1a1a6z.aspx
+	// includes terminating '\0' according to example in https://msdn.microsoft.com/en-us/library/xa1a1a6z.aspx
 	vsprintf_s(msg, n, format, ap);
 
 	final = strf(L"[libui] %hs:%hs:%hs() %hs%hs\n", file, line, func, prefix, msg);
diff --git a/windows/draw.cpp b/windows/draw.cpp
index 6e278fc5..dec6c18f 100644
--- a/windows/draw.cpp
+++ b/windows/draw.cpp
@@ -95,8 +95,8 @@ void freeContext(uiDrawContext *c)
 	if (c->currentClip != NULL)
 		c->currentClip->Release();
 	if (c->states->size() != 0)
-		// TODO userbug()
-		complain("unbalanced save/restore");
+		// TODO do this on other platforms
+		userbug("You did not balance uiDrawSave() and uiDrawRestore() calls.");
 	delete c->states;
 	uiFree(c);
 }
@@ -228,7 +228,9 @@ static ID2D1Brush *makeBrush(uiDrawBrush *b, ID2D1RenderTarget *rt)
 //		TODO
 	}
 
-	complain("invalid brush type %d in makeBrush()", b->Type);
+	// TODO do this on all platforms
+	userbug("Invalid brush type %d given to drawing operation.", b->Type);
+	// TODO dummy brush?
 	return NULL;		// make compiler happy
 }
 
diff --git a/windows/drawpath.cpp b/windows/drawpath.cpp
index 1ae2d8e5..be02b826 100644
--- a/windows/drawpath.cpp
+++ b/windows/drawpath.cpp
@@ -241,7 +241,6 @@ void uiDrawPathEnd(uiDrawPath *p)
 ID2D1PathGeometry *pathGeometry(uiDrawPath *p)
 {
 	if (p->sink != NULL)
-		// TODO userbug()
-		complain("path not ended");
+		userbug("You cannot draw with a uiDrawPath that was not ended. (path: %p)", p);
 	return p->path;
 }
diff --git a/windows/drawtext.cpp b/windows/drawtext.cpp
index b2bd81da..453b4c10 100644
--- a/windows/drawtext.cpp
+++ b/windows/drawtext.cpp
@@ -139,7 +139,7 @@ void attrToDWriteAttr(struct dwriteAttr *attr)
 			break;
 	}
 	if (!found)
-		complain("invalid weight %d passed to attrToDWriteAttr()", attr->weight);
+		userbug("Invalid text weight %d passed to text function.", attr->weight);
 
 	found = false;
 	for (i = 0; ; i++) {
@@ -152,7 +152,7 @@ void attrToDWriteAttr(struct dwriteAttr *attr)
 			break;
 	}
 	if (!found)
-		complain("invalid italic %d passed to attrToDWriteAttr()", attr->italic);
+		userbug("Invalid text italic %d passed to text function.", attr->italic);
 
 	found = false;
 	for (i = 0; ; i++) {
@@ -165,7 +165,8 @@ void attrToDWriteAttr(struct dwriteAttr *attr)
 			break;
 	}
 	if (!found)
-		complain("invalid stretch %d passed to attrToDWriteAttr()", attr->stretch);
+		// TODO on other platforms too
+		userbug("Invalid text stretch %d passed to text function.", attr->stretch);
 }
 
 void dwriteAttrToAttr(struct dwriteAttr *attr)
@@ -204,7 +205,8 @@ void dwriteAttrToAttr(struct dwriteAttr *attr)
 			break;
 	}
 	if (!found)
-		complain("invalid italic %d passed to dwriteAttrToAttr()", attr->ditalic);
+		// these are implbug()s because users shouldn't be able to get here directly; TODO?
+		implbug("invalid italic %d passed to dwriteAttrToAttr()", attr->ditalic);
 
 	found = false;
 	for (i = 0; ; i++) {
@@ -217,7 +219,7 @@ void dwriteAttrToAttr(struct dwriteAttr *attr)
 			break;
 	}
 	if (!found)
-		complain("invalid stretch %d passed to dwriteAttrToAttr()", attr->dstretch);
+		implbug("invalid stretch %d passed to dwriteAttrToAttr()", attr->dstretch);
 }
 
 uiDrawTextFont *uiDrawLoadClosestFont(const uiDrawTextFontDescriptor *desc)
@@ -242,7 +244,7 @@ uiDrawTextFont *uiDrawLoadClosestFont(const uiDrawTextFontDescriptor *desc)
 	if (hr != S_OK)
 		logHRESULT(L"error finding font family", hr);
 	if (!exists)
-		complain("TODO family not found in uiDrawLoadClosestFont()", hr);
+		implbug("TODO family not found in uiDrawLoadClosestFont()", hr);
 	hr = collection->GetFontFamily(index, &family);
 	if (hr != S_OK)
 		logHRESULT(L"error loading font family", hr);
diff --git a/windows/menu.cpp b/windows/menu.cpp
index 89406d7f..484bf756 100644
--- a/windows/menu.cpp
+++ b/windows/menu.cpp
@@ -87,7 +87,7 @@ void uiMenuItemDisable(uiMenuItem *i)
 void uiMenuItemOnClicked(uiMenuItem *i, void (*f)(uiMenuItem *, uiWindow *, void *), void *data)
 {
 	if (i->type == typeQuit)
-		complain("attempt to call uiMenuItemOnClicked() on a Quit item; use uiOnShouldQuit() instead");
+		userbug("You can not call uiMenuItemOnClicked() on a Quit item; use uiOnShouldQuit() instead.");
 	i->onClicked = f;
 	i->onClickedData = data;
 }
@@ -111,7 +111,7 @@ static uiMenuItem *newItem(uiMenu *m, int type, const char *name)
 	uiMenuItem *item;
 
 	if (menusFinalized)
-		complain("attempt to create a new menu item after menus have been finalized");
+		userbug("You can not create a new menu item after menus have been finalized.");
 
 	if (m->len >= m->cap) {
 		m->cap += grow;
@@ -167,7 +167,7 @@ uiMenuItem *uiMenuAppendCheckItem(uiMenu *m, const char *name)
 uiMenuItem *uiMenuAppendQuitItem(uiMenu *m)
 {
 	if (hasQuit)
-		complain("attempt to add multiple Quit menu items");
+		userbug("You can not have multiple Quit menu items in a program.");
 	hasQuit = TRUE;
 	newItem(m, typeSeparator, NULL);
 	return newItem(m, typeQuit, NULL);
@@ -176,7 +176,7 @@ uiMenuItem *uiMenuAppendQuitItem(uiMenu *m)
 uiMenuItem *uiMenuAppendPreferencesItem(uiMenu *m)
 {
 	if (hasPreferences)
-		complain("attempt to add multiple Preferences menu items");
+		userbug("You can not have multiple Preferences menu items in a program.");
 	hasPreferences = TRUE;
 	newItem(m, typeSeparator, NULL);
 	return newItem(m, typePreferences, NULL);
@@ -185,7 +185,8 @@ uiMenuItem *uiMenuAppendPreferencesItem(uiMenu *m)
 uiMenuItem *uiMenuAppendAboutItem(uiMenu *m)
 {
 	if (hasAbout)
-		complain("attempt to add multiple About menu items");
+		// TODO place these userbug strings in a header?
+		userbug("You can not have multiple About menu items in a program.");
 	hasAbout = TRUE;
 	newItem(m, typeSeparator, NULL);
 	return newItem(m, typeAbout, NULL);
@@ -201,7 +202,7 @@ uiMenu *uiNewMenu(const char *name)
 	uiMenu *m;
 
 	if (menusFinalized)
-		complain("attempt to create a new menu after menus have been finalized");
+		userbug("You can not create a new menu after menus have been finalized.");
 	if (len >= cap) {
 		cap += grow;
 		menus = (uiMenu **) uiRealloc(menus, cap * sizeof (uiMenu *), "uiMenu *[]");
@@ -290,7 +291,7 @@ void runMenuEvent(WORD id, uiWindow *w)
 		}
 	}
 	// no match
-	complain("unknown menu ID %hu in runMenuEvent()", id);
+	implbug("unknown menu ID %hu in runMenuEvent()", id);
 
 found:
 	// first toggle checkboxes, if any
@@ -313,7 +314,7 @@ static void freeMenu(uiMenu *m, HMENU submenu)
 			if (item->hmenus[j] == submenu)
 				break;
 		if (j >= item->len)
-			complain("submenu handle %p not found in freeMenu()", submenu);
+			implbug("submenu handle %p not found in freeMenu()", submenu);
 		for (; j < item->len - 1; j++)
 			item->hmenus[j] = item->hmenus[j + 1];
 		item->hmenus[j] = NULL;
@@ -349,7 +350,8 @@ void uninitMenus(void)
 		for (j = 0; j < m->len; j++) {
 			item = m->items[j];
 			if (item->len != 0)
-				complain("menu item %p (%ws) still has uiWindows attached; did you forget to destroy some windows?", item, item->name);
+				// TODO userbug()?
+				implbug("menu item %p (%ws) still has uiWindows attached; did you forget to destroy some windows?", item, item->name);
 			if (item->name != NULL)
 				uiFree(item->name);
 			if (item->hmenus != NULL)
diff --git a/windows/progressbar.cpp b/windows/progressbar.cpp
index 26153f78..2700a790 100644
--- a/windows/progressbar.cpp
+++ b/windows/progressbar.cpp
@@ -33,7 +33,7 @@ static void uiProgressBarMinimumSize(uiWindowsControl *c, intmax_t *width, intma
 void uiProgressBarSetValue(uiProgressBar *p, int value)
 {
 	if (value < 0 || value > 100)
-		complain("value %d out of range in uiProgressBarSetValue()", value);
+		userbug("Value %d is out of range for uiProgressBars.", value);
 	if (value == 100) {			// because we can't 101
 		SendMessageW(p->hwnd, PBM_SETRANGE32, 0, 101);
 		SendMessageW(p->hwnd, PBM_SETPOS, 101, 0);
diff --git a/windows/spinbox.cpp b/windows/spinbox.cpp
index 9118d1d7..a9a9ed4b 100644
--- a/windows/spinbox.cpp
+++ b/windows/spinbox.cpp
@@ -184,7 +184,8 @@ uiSpinbox *uiNewSpinbox(intmax_t min, intmax_t max)
 	uiSpinbox *s;
 
 	if (min >= max)
-		complain("error: min >= max in uiNewSpinbox()");
+		// TODO
+		implbug("error: min >= max in uiNewSpinbox()");
 
 	uiWindowsNewControl(uiSpinbox, s);