Our program works fine with vbulletin which is what we support. We do not claim compatibility with peoples hacks or mods.
I take it your mods doesnt use any mysql connection strings which is probally your problem with your hack in that how and what where it is etc.
Maybe try placing something like this at the top of your vbfoster hack whatever it is.
Content visible to verified customers only.
Make sure you set your vb database name