The only workaround I know of so far is copying the level you want to edit to your mods' Levels\ folder and editing it from there.
Or - if you really want to destroy your main campaign
- here is a patched LSToolFramework.dll with the developer rights protection disabled:
https://dl.dropboxusercontent.com/u/32263228/dos/LSToolFramework.dll(Only works with the v1.0.6 editor)
