Update.
Ran program today to check shows. Didn't crash at all. Qlab was sending midi triggers to Lighting controller for timelines and 3d was running along with audition window from qlab for video. Wav file was present in timeline but muted.
Seems better. Maybe the quicktime crash was a one off?
Programming and synchronising in old version of software and transferring to new version works. Timelines keep timing with wav so this is at least a very temporary solution but trying to actually program synchronised timelines in current version still not possible.
Hope this info helps you!