Format of FGDRIVER VBTCCOPY variable record:
Offset	Size	Description	)
 00h	WORD	source region's left edge
 02h	WORD	source region's right edge
 04h	WORD	source region's top edge
 06h	WORD	source region's bottom edge
 08h	WORD	X coordinate of destination region's upper left corner
 0Ah	WORD	Y coordinate of destination region's upper left corner