Great atmosphere and story, and I think I get the respawn mechanic: workers are being forced back into the complex to shut the thing down with no consideration for their own survival.
I found some issues with the double-jump controls. In particular, my keyboard (just a regular US laptop) apparently can't send space, left, and up at the same time, though all other combinations seem to work. Thankfully, one doesn't have to keep space down after initiating a double jump, so with some practice I managed to figure it out. (The tutorial helped, but I still didn't realize I could use up or down or indeed changing sequences of directions for a while.) Beyond that, game lag (picks up once a few areas have been cleared) sometimes affects how long you can fly, making certain tricky jumps a bit trickier. But then I suppose powered exoskeletons might fail in high radiation environments, so we'll call that a feature :)
Edit: Adding WASD as alternate keys for movement and Shift for jump would help with my keyboard woes and appease folks who prefer directional controls to be on the left.