No problem, happy to try to help though at this point I'm not sure what else I can suggest. The card not being on the HCL makes me dubious about it's compatibility with XP. This is where having another machine would have helped (I realize this is beyond you right now). Try the following:
Remove it both physically and logically (from device manager) on the machine then shutdown Windows
Bring Windows back up minus the card
Shutdown, install the card but do NOT attach the other hard disk, just stick with the regular setup you have
Install drivers if possible
Shutdown
Connect drive(s)
Restart
It could be a matter of it's not ready to have a physical drive yet. Give it a shot. If that doesn't work, sadly I've no other suggestions. Good luck.