Hi Structure, thanks so much for your quick reply. geek uninstaller and revo are for windows only, there is no mac version. I found something similar: App Cleaner for Mac. It cleaned everything, I re-installed poser, changed my account, typed in the serial key and it installed it. but .. same problem again .. same message:

Poser Content Library cannot be displayed because it requires the Adobe Flash Player. Please click below to install.

Get Flash

I am soooo desperate right now ... :( :(