Yes but the logic is incomplete so the walls wont work properly, and gates I've tried, but I can't seem to get them to work, so unless DeeZire has any info on this I think it's impossible to get them to work right.
Walls were in the older versions of Second Wave. You can't use the wall code where you hold and darg the mouse in order to create a wall of your specified length because the code is very buggy. You can howver make it so you can build walls of varying static lengths which is what we did in Second Wave. Walls are very easy to code. Just make a building that doesn't do anything :P You can't however have fancy building and connecting like other RTS games.
Thanks Dee, but I already tried the CheckPointUpdate with the Door open thing and it didn't work the gate opend and then once it opened it disappeared and you could only select it with the drag and drop method.