jmac698: Thanks for that.
nhope. Your perseverance has paid off. I reproduced your problem in the MeGUI preview and fixed the cause, there's a new
version v3.31 in the OP. There's no need to update documentation or spreadsheets, it's only this bug-fix.
mr.duck: Are you trying to use QTGMC in realtime? It's not really designed for that, it's designed to make high quality results to encode into another file (i.e. to make an mp4 or mkv). However, if you have a decent machine and use the multi-threading tips in the documentation you can get realtime SD playback for the quicker settings. Not sure how well your machine would cope with that.