Half-Life 2: DM Sand Defenders Map

You are one of the combine soldiers that are defending small post in the waste desert. In 90 seconds antlions began MASSIVE assault on your post. You must use all of your game skills to survive until reinforcements arrive.
Bugs I had creating this map for anough long time,sure I do all my best to created it without any bugs, but unfortunatly there can be some of them: 1.Some time when you will play, the dropships can no landed on ground, or they can stuck in the air.