I don't seem to always hit zombies when I'm standing right next to them. I find this a little frustrating in what is otherwise a very innovative and fun game.
Are you supposed to get the fifteen kw words in one round? That's practically impossible, as most of the beginnings and endings of kw words don't appear as prompts in the game.
I'm playing the production tutorial and after the view centers on the enemy HQ I cannot scroll back to my units. Must be a bug. Apart from that: please keep working on this! We need more hex-based strategy games!
At first it really irritated me but then I was like "neat puzzles"...got so that by the last level I was actually outthinking myself and making it harder.
Not a bad game overall.
The secret to getting 5m points, in addition to the advice in the top comments, is to get a flashing piece in the mid early game when the screen is full of pieces. That way you can have a x50 multiplier before the first minute is up, and 5m points are inevitable. But if you don't get a nice flashing drop, you might as well restart.