Cant play the undergarden

hi, I bought the over garden from steam for 2 days ago, charged home down there, I thought I downloaded the game, but can neither start or find game in the computer / data, but it is listed on my steam account, ready to play, it does not say that I'm going to install it, because it is already done, need someone cooking or the key to kick-start the game or is there something wrong with the data settings somewhere, a message comes up when I try to start it that it is not available, so how do I do?

one more thing, I have two computers,on these two computers work the game to both download and play,it may give a hint on what is the problem then? i hope,I become insane on this soon,is there anyone here who can answer me soon??!please!!!

I mean I have two computers, in addition to the one I already have, a total of 3, as it does not work on, perhaps it has something to do with the firewall, or do I may have to reinstall steam?