Hey I am using 4.3 and started playing around with the math expression nodes to help clean up my Blueprints. they work fine while the editor is up and running. But when I compile, save, then close and reopen the editor, the math expression nodes clear them selves out. When you click on it, all it shows is the connection between the input and output, it somehow removed the math that was in between the nodes. For right now its not a big loss for me, it was just some basic math, but I can see that it can be a major issue for people who are doing complex math, or vector math. I don’t know if there is something I’m missing like a step to saves these out but if not I just wanted to point out a possible bug.