Hello.
Whenever im playing near the Roman's cab depot i have a stopped train glitched (like all the train packed in one wagon) that lags my game alot,i tried re-install the game and the mods and its does it again after a while,i tried searching for a fix but nothing came up,i played without any mods and it didnt do the glitch.

As far as I know the only way to get rid of the subway trains is to play online with no other players via Windows Live or LAN connection. 

Try installing your mods one by one and you'll probably find out what's causing that train glitch.