I have the same issue as GhostMiner. Nothing happens when I hold the LMB on the apple other than it starting a sound and then pops, but nothing else happens. I can keep doing it but nothing happens. Tried restarting the game a few times, didn't help. Tried both, choosing left and right hand at the beginning, to see if it affected it, but didn't help.
Anyways, the game look awesome, and I like the way it is set up. I just wish I could get past the apple level to see the rest of the game :-)