I have tracked down finnaly a problem with why some of my software has an issue with CPF and will not execute. They are using anti-debugging techniques, and finding dbghelp.dll.
I discovered it while developing my own software, as I am implementing many anti debug techniques.
Could you possibly rename the dll to something else. I notice you guys use PEcompact, possibly you could use PEBundler and bundle the stuff with the cpf.exe so it is not detected.
Also, your dbghelp.dll is quite outdated. You might possibly want to use newest version. 
Cheers, keep up the great work.