prison

Prison is a stupid map. You have to stick together at all times, and if you find yourself capturing a flag on either side of the map you might be so far away from the base you'll die before you get there.

I don't think that's it's dumb, but it can be rough for pugs. My advice is talk a lot.

also, imo, you should stick together most of the time

Yeah, that's WHY it is dumb.  It also has the worst landslide problem of any map.  In 3v3 games for instance, if the 3 manage to get a good kill in against the other 3, then the 2 have to generally withdraw... often being unable to farm experience (The lanes are very far from the towers) or capture flags (Far too easy to 'trap' someone).  This lends itself to either a feeding frenzy, where one team goes 3v0 for a while after getting a triple kill, or in one team severely outlevelling or warscoring the other.

Also, since the two lanes are so close to each other, the winning team very early can start maintaining a large xp margin.

The bottom line is, half the players in a game on Prison lose, and losing on prison is probably the worst map to lose on.

The problem I always have is that as soon as you go back for mana (I play Sedna so have to go back a lot at the start) the enemies take up the lanes instantly and then it's really hard to push back again.
Good communication can only do so much.

Do not venture too far from your towers.

Try to draw the enemy away from their towers.

If you HAVE to run, run through the central tower section, you cannot be chased there.

Ideally - get items which mean you don't have to run

Unless you are rook, on Prison, movement speed = win

I like Prison, it is generally a quick map, although not as strategic, makes a break from Cataract.

Prison you have to stay with your teammates at ALL times.

Are you sure you are talking about the same map? The creeps will always end up at the central towers, in fact you could easily let them come to you, stand in the central towers and gain double xp.