MergeAllFaces is VERY slow if there are more than a few faces in the game.
You can test it with the attached easily.
CP_MergeAllFaces_SuperSlow_V5.zip (465.9 KB)
In V6, it would be great to have the MergeAllFaces a lot faster!
As it was once with Join, that was also very slow and became MUCH faster in V5.