Well it all depends on how complex the DS plans were on geonosis. All we saw was an illustration a.k.a. raw blue prints. Someone still needs to engineer the thing. They probably came up with the idea of the superlaser, but they probably didn't know how to come up with an efficient exhaust system. I think we can still thank Lemelisk for that. His design was very useful in expelling the intense heat of the DS core, as well as inserting proton torpedos if necessary
As for the Maw installation, they would need a top secret location for the construction and testing of the superlaser. According to EU lore, the DS1 was constructed over planet Despayr. Who knows? Maybe GL will include all of that.