I had a lot of problems playing this game because the camera kept moving to the right bottom corner. Based on the other comments this seems to be an issue that only i ran in to. Which makes me think it might be due to my setup (maybe an incompatibility with my mouse driver or VM).
Apart from that as far as a could play it was a fun little tower defense game, for me it was a bit confusing at first that you had to separately pay to unlock a tower before buying one. But apart from that the game was very straightforward and clear.