Repeatable Crash when adding train track to intersection

[DNABeast]

Oh, I'm so excited! I've never had Factorio crash on me before and now I've got a situation where it happens ever time.

I have a screenshot of the piece of rail I was trying to put in. I'd add it from left to right. I'd do it manually (no bots) and when I put the final curve in some signals would start flashing. And then when a train passed through, if it hit the intersection from the left it would crash the game with the log file attached. I did this three times in a row.

I'm running the latest build from steam on a PC (Win 8.1) that's a couple of years old.