INT 16 - PC Tools v5.1+ DESKTOP API - GET ???
AX = FFC4h
Return: AL = ???
BX = segment of scratch space???
CX = segment of stored screen data (section covered by window???)
DX = segment of window parameters for ???
ES:BP -> ???
Note:   available only when popped up in versions prior to 6.0


16FFC4 - PC Tools v5.1+ DESKTOP API - GET ???