Same issue, and I'm not sure what the deal is.  There is an option to disable random objects, but it doesn't seem to work when actually playing the map.

I would like to know that as well. Since the main topic says "Map Editor Questions" I have a new one to ask as well.

I am having a serious issue with the editor not saving changes to the map. Is anyone else having this problem?!? It is so aggravating to try editing a problem that the map I made has, and save it, reload, and the map was not saved to how I changed it. I have tried several different ways to remove a bunch of rivers, that I just put "water" in its place. The rivers are overlayed on the water. I know the water will make it impassable, but that makes it more interesting... Ships will have to be used. (If it works like I want)  Anyway, I have even saved it with two different names, and it still loads up as before I edited it.  This is really upsetting me.  If anyone can, please help.

[UPDATE]  I figured the "river" problem out... I had to put land over the "water" SAVE, Then reload the map so the "river" can then be seen again, use the "River Tool" to edit out the river, and then use the "water tool" to put the "water" where I wanted the original river to be. Thus, creating an impassable river. Quite annoying.  This needs to be fixed.  No other tool will remove a river.