I think I've found the cause of the problem, I use XPlite to remove components I don't use, one component is 'Performance Monitor' if I reinstall that using XPlite, ProcessTamer works, so yeah like you say most likely some DLL issue.

I've just installed ProcessTamer, upon launching the Configuration it'll say the Tray program is running but then instantly says it isn't, despite that fact that it is.

Does ProcessTamer require and specific services to be running? as my XP is highly optimised in that regard, as it is ProcessTamer doesn't seem to be doing anything.