Press space to start the round. Press LMB to fire. As of now, we don't have any upgrades or other towers. Also, we could always use some more members so, if you would like to become an official member of the BTD S team, send me an email at astrobly.abl@gmail.com. (This is not my private email) I notice there is a bug where you can place towers on the track and in water. I also know about the bug where sometimes when you place a tower it place two of them. If you wish to help please conatct the above email.