I had the same problem, and I mailed xylio, and they told me that it's not futuredecks as that does not use the registry, and that it was more likely to be one of my plugins.
Since I use the same install of XP for futuredecks as well as music production, I figured I must have left a .dll lying around that I had uninstalled, but it had not got rid of - hence why there was no registry record.
I started to delve around, got into the plugins folder and deleted all the .dll's, except xylio's own FX, and hey presto! Error was gone!
However, if you're like me using the same partition, it's also possible that a plugin that's not in the FDP folder is causing the error, since I've heard things about plugin shells (like waves plugins have), that can crash FDP, even when the FX are not in the FDP FX folder.
Anyway, long story short, delete or move any FX you have in FDP folder, and see if that solves the problem. If it doesn't, it's time to start un-installing/re-installing plugins (if you use them anywhere else) to find out which ones are crashing FDP.
Also - download CCleaner (google it), as that has a registry cleaning tool, and it's free!
Hope this helps!