You say

"The real tough choice is the HARD level. I've been play testing for some time and I only completed the game once on that level so far!"

But I passed the game at this level, though not without problems, but I did it in 4 hours.

P.S. I do not play very well.

P.P.S. The game has an unpleasant bug. Enemies deal damage, even when the Robot is already on another screen.

Thanks for the information on the bug.  I have noticed this myself, but it's something that I have no control over, as it seems to be the AGD engine that caused this to happen.  Well done for completing the game in HARD level - that is some achievement.