Well that is embarrassing. You are absolutely correct. I just don't remember having to set the variables to false in the past. I withdraw the submission.

Uploaded a mission file with the Effects working. I was able to work around the issue by manually editing the mission file and adding the "Class Effects" into the trigger. If you try and resave this in the editor, the Effect will go away.

Hopefully that helps. Looks like the engine hasn't forgotten what to do, it's just the Trigger or WP "Effect" drop down that has lost it's ability to select it and add text.