Alright, here is my map review:
Terrain: For an escape this map has really bad terrain. It uses no doodads, save the gates which need to be opened. Regarding the tiles, this map is very poor: It uses the dirt tile as the terrain where units must not step(that doesn't make sense? Dirt of death? I could understand quicksand, but then you'd use sand. Dirt?). Put aside the default walkable tile, it uses 3 more which are very rare and usually represent either a "pressure plate" or a checkpoint. All in all I would have to give a 2/5 for terrain.
The gameplay itself is rather dull. The first four levels, as well as the final are a piece of cake and can be passed by 1 player without any lives lost. The fifth level is rather hard because you have units spawning out of nowhere, with no warning and players will surely die at least a few times. This is not the point of an escape map, the point is to more or less know what the trap is and to overcome it, not to mindlessly die 5 times until you are sure how the trap works. Another problem is that the player has unlimited lives and therefore no reason to concentrate on passing the obstacle. All in all a 2/5, sorry.
There were a few bugs as well. The first bug I really found annoying is that you didn't remove the collision of your main units which is the first thing you should do in an escape map. If you play with more then 2 players you have to wait in line that everybody gets through instead of just going all at once. The second bug is regarding the ghost keys, when you have to open the 2 gates. At the map description you said that all keys must be in the 1st slot. The truth is if you want to open the second gate you need to have it in the 2nd slot, which isn't really that big of a problem because you pick them up in that order, but if you die, because they are the same key types and they both drop at the place you died, you can get them mixed up.
Also the map has no background, not even a bad one such as being stranded in hell with a helicopter. And the enemies aren't really logical, you have footmen, mortar teams, knights, peasants and abominations?
To sum up this map deserves a 2/5 at this current state. Look at some professional escape maps, such as polar escape and learn from them.