Following the main game levels, the next obvious set of maps is none other than Rise of the Triad Extreme (aka EROTT). EROTT was originally an expansion for ROTT, but it has since been released as freeware and can be obtained from 3DRealms.
This is one of the coolest resources for such an undocumented add-on expansion pack to a classic FPS! Your maps helped me verify and confirm some secrets and push-wall oddities in some of the levels. Thanks!
If you're interested, please feel free to check out my EROTT guide, which should be part of my name in this comment submission 🙂 I learned and posted really good strategies for every single level of the add-on so anybody can complete each without saving anywhere mid-level, on the highest difficulty setting and it's highly compatible with pistol starts. AFAIK, it's the only guide that covers the expansion. One of my hopes was that people who found EROTT too difficult might find useful information in the guide to make the expansion more accessible and more approachable.
I confess, I am also one of the people who found EROTT a bit too difficult.. or at least frustrating. I eventually rage quit on the Krist Cross level, but reading your guide would have indeed pointed me to the asbestos armour that I was missing.
Is the flame wall part even possible without the asbestos armour? 😀
That annoying firewalls section is in fact doable without the asbestos vest, but it's a real cheap shot in terms of challenge. It essentially boils down to standing in the safe intervals within a very narrow distance range from the fire column in front and/or behind you. You have to be so precise in where you stand. Go even the slightest out of the range in either direction and you're toast, as one boss so eloquently put it. It also doesn't help that the most recommended character, Thi Barrett, is one of the faster ones, making it pretty easy to accidentally get too close. For no-saving, it'll be a nightmare to do without the vest of course; however, if you're save spamming, it's a major annoyance at best.
This kind of fire column obstacle later comes back in one of the hardest levels, right at the very end to potentially break the player for good. Luckily, it isn't nearly as drawn-out.