I have 2 computers, each running Win7 64 and K-Lite Mega 7.7.5 32bit and K-Lite X64 5.2.0. I have mirrored all of the codec settings from one computer to the other and for some unknown reason I am having trouble using the extreme engine for mp4's and mkv's on one of the computers. It doesn't give any error messages or appear to even try generating any screenshots, almost immediately says failed. The exact same files work fine with engine 2 and the extreme engine on the other computer. Any ideas?