This is a very good map, all the more impressive given it's size. I can't criticize much. Itemdrops and creeps are fine.
Some stuff I think is worth noting in particular:
-Random creeps, but without a big impact on gameplay.
-The starting situation in 4v4 is slightly different for ech player. One of the "flank" players will have an easier time to expand then the other, but on a team basis it is fair.
-I'm not a biggest fan of overly safe expansions. But given that they are stable on many 4v4 maps, I cant blame you for doing so.
-The middle creep can aggro on reinforcing units. It's not ideal, but unlikely that it will happen in the early game (it seem like the map should more lean towards two 2v2s on each side instead of 4v1 strategies). By the mid-lategame, I imagine there will be big fights in the middle anyway.
Map Approved.