Crashes in WoW

I have returned to multiboxing after a couple of years and I have several problems with ISboxer and Innerspace that I haven't experienced before.
The game sometimes just crashes when I click on the "activate broadcasting" icon and when I launch the game I sometimes get the error message "Failed To Find a suitable Display Device. Exiting Program."

Does smbd experience similiar problems and knows how to fix it?
Which patch of ISboxer and Innerspace works the best for you on Wotlk?

Any help would be very appreciated! I have already asked in the ISboxer forum but unfortunately nobody replied...