Format of License Service SLSUPDATE structure:
Offset	Size	Description	)
 00h	DWORD	(ret) status code
 04h	DWORD	(call) handle identifying license context
 08h	DWORD	(call) total units consumed
 0Ch	DWORD	additional units required
 10h	DWORD	address of comment string
 14h	DWORD	address of SLSCHALLENGE structure (see #02851)