It seems that, with every new version, you fix some problems but actively create even more!
No overruns with three lossless exports here - a :55 and 7:25 AVI and a :55 MOV independently - using beta version 6.23, which should be out shortly. However, when those clips were combined and then lossless-exported to a video file, clip #3 was either blank, out of sync or lacked some audio when played, depending upon where play was begun.
NCH shares improvements regularly and that's to their credit in my book. They are also more responsive to fixing problems than are some other companies.
E.g.: even after extensive testing, Windows 8 broke MS's handy FAX utility. It wasn't repaired until the release of W10. In that major release, DUN was unusable. The most recent version (not beta) of an emulator that has been successfully updated many times here locked up, and hosed the PC's file system.
Reworking of software and shorter testing times invites regressions/bugs. Nature of the beast.?