Quicktime export does not work: after 90 minutes "mixing down" and sub ten minute edited compilation, it produces either a 1kb blank file or no file at all. Incidentally, MEPMX (18) disappointingly takes about 50% longer than MEP17 to mixdown. Also Quicktime export now no longer works in MEP17. I have reinstalled Quicktime.
My hardware: 4 core PC, 6GB RAM , 3TB HDs Windows 7, 64bit
There are also many other problems with MEPMX 18 but this is the most annoying one...