This game is amazing!!
There are a few things I don't like though.
1: When I delete a beam, if one falls, it counts as a tower failure.
2: There is no "Sandbox" mode - it would be cool if there was a mode that let you rebuild off the ruins of a collapsed tower (if the tower falls, then a tower can be built using the fallen tower as a foundation), or reset it so that you'd have a clean slate to practice.
3: There should be a warning sound or something to alert you to dangerous stresses on the beams.
4: A "Speed" button or something. As in, when there is a beam that is under dangerous levels of stress, it is horrible to not be able to reach the danger zone fast enough. So your tower basically just starts sinking on the screen, and one can't get to the breach fast enough to repair it.
Other than that though, this game is teh rawkzorz!