Excellent. A really good level, with a great knowledge of the current editing programs and a total use of the possibilities they offer.
An intense combat very old style Duke Nukem and with some (delicious) touches of logical puzzles Half-Life 1 style.
The only two points I don't like are:
1 - It's too aggressive even on the easy level. There is enough ammo, but there is a lack of more first aid kits and more armor, and the player should be provided with the most powerful weapons earlier and more easily in the level (then you can ration the ammo if you want to make it more difficult).
2 - The path and the order in which the player must perform the actions, is confusing, unintuitive and complicates a lot the development of the game during the second half of it (the textual help on screen, help, but are not enough). Maybe you should expand the readme.txt and add the background and the necessary indications.
The idea that the path is not linear and that the scenarios are reused again and again for different reasons and with different results, and that the same scenario accumulates damage, is well resolved and works great.
On the other hand, some bobby traps are really perverse and abusive (yes designer, don't act surprised, you already know what they are ;-)
At the very least, you could provide plenty of first aid kits and armor in the vicinity.
For the rest, as already said, the level is really very good, one of the best I've seen in recent months and I don't even want to think about the immense amount of work it must have cost the author to do it. Only the architecture, lighting and decoration alone require more than a week of full time work. That's not counting with the choreography of the fights (here the author has not simply put a lot of enemies in each corner, but on the contrary, everything is very well measured and timed) and all the orchestration of the triggers.
In short: an excellent level but with a few adjustments, it would be almost perfect and that in its development reminds you of the old and mythical FPS of the golden age of the beginning of this century. If you are a Quake fan you MUST PLAY IT....