Wow! Now that was a brilliantly executed 2 level mini campaign. It was very well made. While I think some Zombies and Headcrabs lesser would've been acceptable as well was it still good the way it was.

Personally I believe this package could've been better if you would've shown some pre-cascade scenario by collecting or delivering something to your fellow scientists to show cast how they actually worked on XEN before things went to hell, a golden opportunity here seeing how it is not Black Mesa for a change.
Perhaps that's something to consider should you expand upon it. I'd love to see a proper Intro with 1 or 2 custom voice sentences and a minor purpose.

the 1st map had some minor lag after the lights were turned on again. See if you can optimize it a bit. The pit being a perfect square leading to the XEN Crystal was also slightly disappointing. Surely you can come up with some better brush work.

All in all was it a very great map pack. Short but great. I'd love to see a continuation of this. Turning this into a fully fletched mod.

Ps: Is this mappack of yours a remake of the Hl1 Map pack with the same name? If so do you still have it? I'd love to get my hands on the HL1 Version of this seeing how all known download links vanished years ago!