Wow! There was a huge hole in my logic here. The delayed shifts opened the door to having multiple shifts marked as active. The instantaneous shift was cancelling the delay on the other one, and both shifts ran through the the teleportation routine together. Therefore, when the change in X was added to the map, both values were added in!
Below is a direct link to a fixed version for you to test Plural. I need to notify Ultigonio of this fix and make sure that I'm not ruining the level he's developing. If it's a problem for him I may need to be more creative.
KS+ 1.2.0 beta* 4 MB
*There was previously a 1.2.0 beta for single-pass rendering KS+. This is not it.
Edit: Ahh! I found another mistake in the timed-shift code (see image.) The top line will let the program act only on the timed-shift that has expired. The bottom line will let the program act on all timed-shifts if one of them has expired. The top line is the one I should have used. Fixing this will give dramatically different behavior if the shifts don't cause the screen to switch, or more than one type; A, B, or C; is used as timed-shifts on the same screen. Example: A row of Shift-A set to move the character one tile up after 1 second will act once in the current version. If I fix it, it will act for each Shift-A you touched as they expire.
Point is I don't want to change this until I know I'm not destroying all of Ultigonio's hard work.