as it turns out, you need a payload hud or people get stuck in carts. so this is the final version, with plr hud instead of sd hud.
i know a lot of improvements could be made, i tried an entirely new layout but couldn't really come up with anything, and wanted to make an extension to last into a spawn courtyard, but didn't have time to make and test it. so this is the final version.
if anyone is interested, i can release the logic (i already have it isolated into a vmf)