this seems like some odd behavior, i'd be surprised if it's related to the version of Vixen, as 2.1.1.0 is pretty solid. Are you running same sequence files that you would've run in the past with vix 2.0 - ie, have you created newer sequences, maybe larger (for example adding lots of channels for pixels)? Are you possibly running into memory issues (I've seen program scheduler crash/stop when I tried to incorporate some very large sequences that ran OK by themselves). If you're having issues with output to the lights, perhaps check the output plugins (you don't mention what you're using - renard, dmx, e1.31, etc), check the physical connections, is it possible something is happening at the controller side. Sorry I can't help with 2.0 - good luck.