why is it so glitchy?
I'm going to quote the post you just replied to for you:
"IMPORTANT: I don't know what effect this map may have on your device. It's far from the origin and glitchy as hell."
I moved far from the origin point in the Editor and built the map there. The large distance seems to result in funky bahaviour.
But without knowing how the game actually handles this distance, I can't tell you exactly why it is so glitchy, just how I got it to be so.