I find the editor pretty easy to use.
Problem is, my saved terrains keep getting corrupted texture materials, I've lost quite a bit of work this way, notably my forest. Once the problem occurs you can't paint or unpaint the corrupted sections without crashing the editor so I decided to abandon it after much experimentation to recover it.
I've given up with terrains for the moment and am building a thieves den. Very simple and fun to create buildings.. wish I could say the same about dialogue however.
Does anyone know if you can reset local variables in the editor? It took me a number of hours to realize that reloading the level didn't clear dialogue variables. I could not figure out why my dialogues were triggering almost randomly.. until I re-opened the editor and everything worked.