v6.0.15 update
New GUI commands added:
GUI = LOADGUI("menu.png", "menu_colormap.png")
SHOWGUI(GUI)
HIT = CALLGUI(GUI, X, Y)
LOADGUI loads a visible menu image plus a color-coded hitmap. The hitmap is converted at build time, so the full overlay image is not stored in ROM.
SHOWGUI draws the GUI at 0,0.
CALLGUI returns the color code under a position, useful for buttons and menu areas.
Also fixed 32X mouse rendering: the cursor is now drawn safely at frame end, preventing trails, flicker, and broken text output.