Thanks for playing!
Do you mean you pressed C in the editor and it didn't delete the block you were on?
I think it's a fair point to have left click select the guys, originally I thought of left click for camera controls and right click for everything else, but I guess this way it would be also easier to tell them to merge.
And yeah, I've yet to bring mouse controls to the editor and keyboard controls everywhere else (Esc to open side menu, R to retry etc)