You can always write own (self use)plugins for wpForo using current available hooks, just search for hooks in whole project and use them. However don't put these plugins for public use. Because wpForo hook system is under active development, those are being changed with each release and people will get lots of error and their sites may stop working. There is no API documentation yet, probably it may be available with 2.x version when the core hook system becomes stable.

Thx, but do you have an example? So i have no idea where  i must write and save my plugin.

lg Chris