I'm making a test map just learning how to use the editor and I've created a memory leak somehow. RAM usage just raises while doing nothing. It doesn't happen in other modules so I don't think it is the editor its self?

Is there anything I can do to find what has caused it?

I just tested it in-game, no memory leak. So it is something with the editor then.

I remember this issue from my early days but can't recall the concrete cause, but it was probably related to an object script. Have you written any in your module?

the only script I had added so far was for a simple dialog.

It started after trying to place a destroyed ship into the map, but even after removing it the memory leak is still there.

I'd always go for scripts first, even small mistakes can lead to spectacular effects sometimes. Otherwise, try disabling other parts of the mod, added around the time of the ship placement, and see if anything changes. Hard to say what it could be.

If you had deleted any creatures during your editor session, this would have been the cause. Restarting the editor remedies the issue.