bug in map editor or I'm doing something wrong.

Greetings.

Recently I've started working on a map that hopefully going to be released soon, however, I came across this... thing, when you import a mesh, it always has a rotation no matter what I set at object rotation.
At rotation, the W has a value no matter what. When I click into it and press 0 and click out of the box (still on the UI) it's fine, but as soon as I click into the 3D area (I wanna rotate the camera or something) it snaps back.

Gfycat Video - Click to Play - Direct Link

(Media doesn't seem to play at me, it shows the issue shortly in a GIF)
If anyone knows a solution for this please help me out.

Things I've tried:
Save the map and load back when the rotation is good - Snapped back immediately
Edit object rotation in the files - Object invisible (?)

Thank you for reading