I've recently stumbled across an error, which could be affected by a recent CT Fusion update in the past years.

So, here is what is happening:

This is from a static platform engine in which it has reverse gravity. The pink line is the players feet.
This is normal, from just standing on any part of the backdrop.

In THIS pic, the player is getting caught in part of the backdrop here off the edge. This is NOT normal.
As I have tested an an older .EXE build of my static platform engine, this error did NOT happen at all.

The 2nd pic shows that the player is STILL on the platform, but on the edge. So for whatever reason, it's making the player move up 1 pixel into the backdrop.
Interestingly enough, this error does not happen when the player has normal gravity standing on a backdrop.

I was wondering what could be causing this, and what the case of this is?

EDIT: Here is the MFA file of the platform engine in question.
It IS an old mfa, from earlier CT Fusion 2.5. Perhaps even before v2.5.
(You get the Select language menu when you open it up.)

So that is why I question if it had anything to do with the new format in v2.5+. The old EXE build does NOT have this issue. But when you build this MFA in the latest 2.5 build, you DO get the error I have mentioned above. I have no clue why.