New user just having a play, using one 10s clip dragged to timeline, then again and this time applied reverse. Export to mp4 and when it hits the reversed clip boy does it slow down to around 1/240th the previous speed. Happens around the 50% mark which confirms its rendering the reversed clip.
Previous render - 2 clips both normal - to mp4 took around 0.5s.
Next render - 1 normal other reversed - to mp4 took 1m59s.
When it eventually completed it played perfect.
Personally not too bothered as I seldom if ever use reverse.
Wonder--- I loaded said clip into *****link editor, reversed it, rendered to mp4, loaded to VP, rendered just perfect, not quite <1s but close. This is how I will go the next time I want a reversed piece, but don't really know whats up with VP, I'm sure it should not take 240 times longer!!!..