Additional Ulvhelm Battle Arena Pieces

I found the Ulvhelm Battle Arena and I absolutely love it. However, I really wanted working gates, and I found a way to attach the gates such that they can swing to the inside or outside, and the entrance can now act as an airlock. The gates are only patterned on one side, but they can be taken out and turned 180 degrees at any time. Alternatively, you can print them at a negative Z value to split them in half and then glue the halves together. Additionally, the stair entrance into the arena being shorter than all of the other pieces was driving me nuts. It means that you have to have the stairs in exact pairs exactly across from each other. So I took the stairs and embedded them in the straight wall. Now the combined piece can be placed anywhere the other straights can!