The Unknown Castle (My First Ever Level)

[Ongka]

Pretty nice for your first map!

There are many overlapping textures and holes which could be covered by a welder. Most places are pitch black and I didn't find as many light sources as i had tinderboxes. The hole in the ceiling is covered by another texture. You could have used some particle effects. The planes were too small and looked strange, you could've set the tile amount to something like 0.5 or lower.
The environment could be more enhanced to get a better atmosphere.
Don't put too much keys in a map, or it will get monotonous.
Make puzzles and parts were the player has to think of what to do next.

Use lower values for impulses, for example at the part with

Spoiler below!

the "exploding" cabinet/door.

But i gotta say, I enjoyed your map!
I really liked the part with

Spoiler below!

the patrolling brute.

I didn't know what to do first, but i managed to stay undetected.
The ending was different from the usual endings. Short, but finally a map where you

Spoiler below!

escape from the castle.

I think you have potential to make good maps.
Try to improve your map with all my criticism.

Sincerely,

Ongka