I remember playing this alone. Satou's maps and mods are very nice, and always interesting; his Half-Life 2 mod Mistake of Pythagoras was amazing. This had an awesome turn with classic 'gray alien' UFOs and new enemies/weapons.
I wanted to convert PEACES LIKE US, his other Half-Life mod featuring an alternate timeline where scientists discovered the Xen aliens and became friends with them, but the military still objected. It featured no original coding, just aliens that wouldn't attack, but the atmosphere was fun and the scripted scenes were awesome. However, I didn't know how to professionally convert mods, even if it was a very easy one.