As a learning level in which to sharpen your skills it's ..... adequate. So far you've gotten the hang of basic room-type sectors, doors, lighting, and columns. Now on to windows, stairs, outdoor areas, lifts, sectors at different heights, etc. Also, unless it's a deathmatch map, remember to include an exit.
Anyway, Crusade is ok for a first try :)
The texturing looks like .... how do I put this delicately? ..... lizard guano that's been baking in the hot sun before being trampled by a herd of frenzied elephants. I'm sure you were just experimenting, but one early lesson is to define a theme (e.g., tech-base, hellish, medieval, etc.) and stick with it when texturing and using flats.
Keep at it, and in 3 days you should be able to map as good as, well ... me!
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