Format of internal K3 structure:
Offset	Size	Description	)
 00h  3 BYTEs	signature "K3$"
 03h	BYTE	length of structure, including this byte and signature
 04h	WORD	compiler switch option flags A (see #00609)
 06h	WORD	compiler switch option flags B (see #00610)
 08h	BYTE	internal flags A (see #00611)
 09h	BYTE	internal flags B (see #00612)
 0Ah	WORD	DOS version recorded at startup
 0Ch	WORD	"ActTypeSpeed"
 0Eh	WORD	last Keyboard-ID sent
		41ABh translated, 83ABh native (pass-through)
 10h	WORD	offset of K3TAB Special
 12h	WORD	offset of K3TAB German
 14h	WORD	offset of K3TAB Alt
 16h	WORD	offset of K3TAB AltGr
 18h	WORD	offset of K3TAB Ctrl
 1Ah	WORD	offset of K3TAB NPad
 1Ch	WORD	offset of K3TAB CtrlNPad
 1Eh	WORD	offset of K3TAB AltNPad
 20h	WORD	offset of K3TAB ApoTbl or 0000h
 22h	WORD	offset of K3TAB UmlautTbl or 0000h
 24h	WORD	offset of K3TAB UmlautTblExp or 0000h
 26h	WORD	length of video mode table
 28h	WORD	offset of VidMdTbl or 0000h
 2Ah	BYTE	'$' end marker