IPX Interrupts: DOS vs Windows (HELP Pls)

Good day all..

I am attempting to make use of IPX routined that access and
manipulate interrupts. I am using the routines supplied by
Danial Parnell. See : http://minyos.xx.rmit.edu.au/~s921878/ipx.html
These are Novells standard Netware calls. From a DOS app,
it works like a charm, however, from a Windows app, certain calls
return invalid data, or simply reboot my PC.
I have converted the register calls as specified in Borlands Help
ie: TRegisters, and Initialization of components before Intr calls.
..and am now at a loss

I would appreciate any insight which may alleviate my immediate dilemma.

Thanking you in advance,
  James Burroughs :-)