I just released version 0.3.0, and have changed the project status to Alpha. Made some major updates, but the best news of all: I'm getting feedback from people! Yes, people are actually playing and testing! Also, want to give a shout-out to our first member mar77i, thanks for joining!
Extra tower levels, movelist file, enemy traits, and more! Check it out!
I've decided to go for 800x600 resolution and it's turning out to be a great choice, I think. Paths are now visible. Squares are gone! (Mostly.) Movelist is simplified, and deselecting towers to place implemented.
Some asked on pygame.org to get screen sizing working (1440x900's a little big), so I have preliminary screen sizing up and running. Widths 1440 and 1280 work quite well.
V0.2.1 is the first public release. Project is also on http://www.pygame.org