I've been playing a new mod I made and it seems to be glitching like crazy when I play against people on 4.1 (I'm on 4.2). People on the older version say they don't see the glitches.

The glitches involve moving objects ignoring all physics for one turn then returning to their correct place the turn after and players warping from one place to another.

It could, in theory just be the mod, but I've made a lot of mods and I haven't come across this issue before. Seems to be amplified by having longer turn frames too.

Hmmm, is it one that uses the new object limit?

Yes it is, pchkotest9.tbm is the most recent version of it. Haven't had problems with any of the other mods I've done with more objects though.

The glitches aren't apparent in free play either.

Are you sure users of 4.1 have the same mod as you? Ive had this problem playing someone who is using 4.1 when i'm using 3.99, the mods were different but with the same name, so there were objects that I couldnt see that made it glitch like crazy

The mods you were playing were the same mod, but versions 4.1 and above can have more objects per mod. So you were playing on an outdated version and couldn't see all the objects (which is why you were glitching).