From LightWiki

This entry is pasted from Mike Scaramozzino's reply in the NewTek forum:

"I think the old 8.5 workaround was to set your end frame longer than you needed, then stop the preview before it finishes. Then copy the /Applications/LightWave/Programs/Current Preview.mov file to another location and open it in QuickTime... It was a pain, but it worked..."