I'm new to CNC but am faced with trying to get the compact 5 in my school running. We have a number of computers we could control it with but i can't get it to work with the XP based systems (we don't have the win 98 computer that previously ran it anymore).
It is my understanding that XP doesn't drive the parallel port in "real time" and you may need a special driver to get it to do so.
There have been many people who've not had fun trying to make CNC stuff work on XP and have had to resort to dedicated "older machines" or else pay to have a computer expert perform magic to get XP to work. Moreover a lot of 16 and 32 bit DOS based software won't work on XP as, at best, it has 'psuedo DOS'.
Simply put, if the machine worked fine on Win 98, why did you bother to mess with XP???
If it were mine, I'd simply find a dedicated 98 box to run it in a machine specific fashion or upgrade your software to an XP version of same if one exists.