Right, so here it is, my first map to be uploaded to forgehub.com.
It is an infection map called Strategic Retreat. It is named Strategic Ret. on Halo and the Bungie forums and Strategic Retreat is too big a word.
The map is on foundry and effectively uses all of Foundry's ground space.
I will talk you through the map with each screenshot as there are many showing almost all parts of the map. Enjoy!:

So this is where the humans will spawn at the start of evry round. It is completely empty as the fighting shouldn't happen for a while yet. The window is blocked so you must turn out into the corridor.

Upon reaching the corridor you will have a visual on the zombies through the shield door. You are protected, for now. Turn right through the open door into the main part of foundry. You will not want to fight the zombies yet as the gametype that I have also designed for this game (and recomend you use) starts humans with magnums and the alpha zombies with battle rifles, overshields and damge resistance. But as the apha zombies have 50% you have time enough to get away and find some superior firepower.

Once outside i would recomend running through the open doors in the middle of the map as these will "close" after 30 seconds. The turrets placed on the balcony are not for human use, these are for the alpha zombies, giving them the ability to mop up any human stragglers who didn't proceed through the wall.

An overveiw of the first section of the map.

You must run through these open "doors" within 30 seconds or walls will merge within them locking you out.

For any stragglers who didn't make it through the wall in time (this is quite unlikely) at 45 seconds in, the warthog will spawn, which might keep you alive for a short amount of time. The zombies route over the wall (stairs and tunnel) will spawn after 60 seconds.

But by this time however, the humans should have suited up and prepared a defense in the armoury (second section of the map)...

Under the zombie's tunnel, you may have noticed a small pile of fusion coils and 2 grav lifts. These act as a switch that the humans can use to their advantage by destroying them causing falling fusion coils to spawn on the attacking zombies...

This man cannon will spawn with the armoury after a length of time allowing you to access the next section.

Heres 2 overveiws of the final main section, where the humans can make a final stand:

And Finally, this is the last room. The one way teleport will lead to the zombie spawn corridor for a "blue room" type of fight at the end as the any spawning zombies will become locked in their corridor after the 180 seconds mark. Also in the gametype each round lasts 4 minutes. I did this because i personaly do not enjoy infection games that reach a stalemate and go on for stupid amounts of time. however i do appreciate that some peoples taste's will favour this type of play so all that needs to be done to the map in forge to stop the zombies becoming locked in, is to delete the 2 man cannons that spawn in the middle of the back corridor and change the round time limit to unlimited.

To download Strategic Retreat(map): Bungie.net : Community : Forum Topic Listing : Forum Reply Listing
To download Suit Up(gametype):Bungie.net : Community : Forum Topic Listing : Forum Reply Listing

Bearing in mind that this is my first map post o forgehub.com all comments, posotive and negative appreaciated, thanks.