OK. First post here on the forum. Because it's in alpha, i'm not gonna complain about the graphics, the missing of hotkeys for building stuff, the missing of tooltips when putting your mouse on stuff. The biggest problem I have encountered is that the units' AI path finding is really ridiculously terrible. Even if there's a small structure in the way of the unit it will go head to head and collide with the structure and keep turning in weird loops. I have to right click onto an empty ground using either shift to queue up some move commands or just simply right click once. Programmers at Uber I hope you are working on the path finding of AI. This needs to be fixed asap.
If you'd look at the patch notes then you could see that they are improving the path finding with each patch. It already got alot better and will get alot better. It's an alpha after all. Just a question: have you ever played any RTS games before? I'm just curious.
You should see the pathing in some other games. It's even worse than in PA right now, althought those games are finnished, so calling it ridiculously terrible is a bit harsh. But you are right that it needs alot of improvement.
Compared to other "Alpha"s from the AAA titles this is was first released in a pre alpha state, at the moment it is VERY early alpha. Patch notes are good to have a read through if your wanting to see the progress made by Uber.
You have to use engineers (fabricators) to salvage something. Pressing DEL will just destroy the building. Might be a debugging hotkey.
You can also select a tank and shoot the debris. SC2 uses the same technical concept for pathfinding as PA does. PA is just horribly unfinished. Wait a few month and it will work just like in SC2.