The editor is loaded in through the game is it not? Plus it crashes on custom maps too as I tried it out on one of the UK which had the same effect... Havent tried other custom maps but felt the same results would have happened.
I have this issue too but found out that if you revert to 1.6.0 then the issue is gone so it looks like whatever you lot changed in 1.6.1 is what broke the tools. The issue in question is with the elevation tool crashing the game when in use.