I'm getting a CTD crash too when trying to play, view, edit - Single replay, Multiple replays, Each environment, Multi Environment TPs.
Ok, just tried something with different results:
Selected 9 replays from a Valley map made in MP4.1 - They all loaded and played (although without the meditracker tracks they should have, but that's another issue). Then loaded one replay from the same map and it loaded and played (again without mediatracker tracks though)
Next, I tried loading 9 replays from a Valley map made in MP4.0 and the game instantly Crashed to Desktop.
Also, on subject of replays, checking the box [Enable Multiple Selections] then clicking the [Select All] button, selects all the replays in a folder but does not offer a "Launch Option". If you first select one track, then click the [Select All] button then a launch option does appear.
[
EDIT-Dec.09 2018 - RE: Replay CTD] Now I'm only getting a replay crash on one track, and the game crashes even when I try to load the track.
This is the Track that crashes:
V007-CornerToCorner2