Well, i managed to play the map a couple times, first time it ended up 3-0 for defenders, no chance for attackers, second time 3-1 for attackers but i'm not sure teams were balanced.
I think so far there are some things to tweak: 1-i've seen 2-3 times attackers write they spawned directly at flag, looks like they spawned at defenders' entry points; i have no clue why this happens, so aside from rethinking all entry points (needed, someone correctly noted attackers need to cross a def spawn are to get to the flag) i don't know how to fix it.
2-reduce and straighten the underground tunnels
3-add adifferent path to flag for attackers
i'll wait a bit more to see if anything else come up before editing