This week the 4th alpha release made it out. It is the first release that I have been able to package and send to testers to use at home. It was an important milestone because there is now too much content in the game to do a thorough in-house test. In the future, I will have to test specific pieces of the game in-house and let testers go through it more thoroughly at home.
Good observations and ideas have already started to come back from testers. This will help drive the next milestone, which will focus more on content creation. Retrobooster needs more and better levels and enemies. There are also plenty of things to improve in the interfaces.
As a bonus, I was able to send Retrobooster to Kevin Meinert of Subatomicglue. He has agreed to work on music for the game. I already have some of his older tracks in the game and testers often think they were made especially for it, so his music seems to be a good fit.