Your blu team_train_watcher is missing a few things. Compare with your red one and you should be able to fill them in.
Blu's final path_track has identical outputs to red's, so you've made it impossible for blu to win the game. You need to change the first output so it sends CaptureCurrentCP to ssplr_
blu_pushzone and the last output so it sends SetOwner 3 to cp_
blu.
Your team_round_timer enables red's push zone, but not blu's. Both start disabled, so it's no wonder blu's cart doesn't move.
These are just the things I could spot on my own, so it's possible there are more. Just make sure that, if you're going to forgo learning the logic on your own and copy straight from A Boojum Snark's library instead, copy it correctly next time...