can't find interface on Mac

I wrote a little filebrowser on PC with BlitzMax on now i want to transfer it to my iMac. I installed Blitzmax and BlitzGui and XCode and rebuild the modules to see if everything is o.k with the install. It works! But now i take my source from PC to Mac and I get the error message

'can't find interface for module 'volumes'

I use Bruceys volumes.mod - but i can't see what i have to change on the Mac side.

Thx for a little help