You cannot play alone, you need at least 2 players to play. If you play alone, it will just sit there, you can just test some heroes this way, I made it like that so I could change the way the victory trigger works so it is more efficient. If you want I could add in -test1, -test2, -test3, etc. for testing creeps in the next version I release so as you can test towers and stuff. This map is a tower wars, not a tower defense. You need more than 1 person to play :/ sorry if it's hard to understand.
EDIT: i would also add in when you choose game modes maybe a -test game mode so that the -test1, -test2, -test3, etc. works so as not to work while in regular game mode or else people would be able to cheat and get free gold.