The original by 3DRealms is free on GOG, btw. https://www.gog.com/game/shadow_warrior_complete
I have the reboot, but I don't think I'm far along. Something always comes up and distracts me and I end up playing something else. What's really confused me is the UI and the perks screen, so I hope they've fixed that. Also got stuck several times because I couldn't figure out how to break those crystals or whatever they are.
That's happened to me, too (one of the drawbacks to not playing straight through). I've had to look up how to break the crystals more than once (you have to use one of the powers, btw...the one that is like a power thrust).
I also found the upgrade menus to be in need of a little streamlining.
For me (and I know I'm mostly alone here, because I've voiced the same issue in other threads and been told I was wrong), one of the biggest hindrances to playing is the size of the levels. They take a couple of hours to finish for me (mostly because I like to find the secrets). That's a lot to decide to sit down and undertake any more.
It's not a complaint, per se, but these longer levels do keep me from jumping back in and finishing games that I otherwise love.
And, for the most part, I really love the first Shadow Warrior. I hope I can finish it one of these days!