Okay, from everyone's feedback, I will put together a post award type of system.
I will look into some converters for icash and ishop, provided they still exist on vBulletin.org, I know a bunch of them have been abandoned and removed.... If anyone can email me a copy of these hacks I can work on conversions faster (next best thing would be phpmyadmin access to your databases...)
Also, I am still putting together what a companion shop would include, however a full-blown project purchasing system (like what vbulletin and others use for real online sales) is in the works, but will most likely not be a free hack due to the size and complexity. This is meant for using in other hacks such as vBookie (confirmed) and some other things I will release later.
Look back tomorrow for the update

(Dont forget to update to today's v1.1 for the time being!)
Edit: Legacy or the new postbits should still show credits, as well as custom styles provided they still contain the $template_hook variable. If that is not there then the plugin cannot insert it into your postbit, and it will have to be added manually. Same goes for any custom profile edits. The instructions for manual inserts to both of them are located
in this post.