This map is created very bad with no effort put in, or maybe there is.
In this map, you can do nothing but just eliminate the enemy, no victory or defeat conditions. The monster just repeatedly spawn and spawn like you say, there is no ending. From the preview image of the map, not even going in, the terrain seems to be very bad. I used two custom heroes which has a "Godly" ability which instantly killed the trolls, structures and Dreadlord. No cooldown for the abilities.
Game just keep on spawning the same units all over and over again, the Trolls & Dreadlord, which simply bored the game. Spotted some Green Icons, which needs to be fix. No Quest Log (F9), nothing.
Many of the problems have been spotted by me, this map requires a huge change before approve.