@zbidou72, this is incredible! I adored the original and it was such a joy to see it fleshed out and finessed this way. It feels so much better like this, Alkaline was a great fit!
As much as I love this map to bits, there are some significant issues I think could be resolved
One little thing really aggravates in the junkyard below the big crane — these big horizontal barrel brushes (screenshot below) are extremely hard to scale, auto-pilot navigation ends up with player sliding at odd angles. This is especially infuriating in the middle of the most unforgiving battle where there is nowhere to evade the ground level onslaught other than by going up (and even then you still spend huge linear tracts without substantial cover). The whole arena is IMO brutally unfair, the only viable strategy I could find was to make it across the yard and finding a crate at the other end where I could take pot shots out of a small gap without fiends or projectiles funneling in, which feels like cheating. I feel like there could be other optimisations to make the geometry more tactically useful to the player, but the barrel brushes feel like a bug.
My other mechanical complaint regards 'time to bust some valves'… It's a very cryptic message and AFAIK the first time flavour text is used to give the player an imperative instruction they need to progress. At the same time, it doesn't come across with the tone of an instruction, and it takes some imagination to realise what the valves are. As a quick fix I'd change the messaging to be either more strategically instructive ("break the valves to get the key") or immersive somehow (I didn't know that boats have valves on pipes on deck and I've no idea why I would want to break them), and give the message a repeatable, larger trigger area; I'd also make the valves far more prominent: the level is so full of gorgeous, consumately detailed brushwork, so it's completely unintuitive that these essential interactive elements don't even grok as that, instead looking like undifferentiated extensions of the pipes they're attached to. Maybe something as simple as a different texture would be enough? In any case, they need to stand out.
As a minor point, the area immediately preceding that — the hangar — also has significant triggers & scripting that aren't immediately clear. A lot of buttons whose crucial effects aren't visible from the place you press them. I'm not sure the best way to address that but I think it undermines player confidence and narrative flow: up until that point we've explored & fought through several huge discrete areas, we just had the epic quad drop from the crane into the hanger… the moment from there on should really feel like tying together all the disparate areas of the map, having a breather while we see some cool animations play out to underline that we're now moving in to the end game. But it doesn't feel like that, because interactive elements are everywhere, pathfinding is tough, and the significant scripted outcomes aren't fully appreciable from where they're triggered.
Hope this doesn't come across too harsh. I really love your work and I'm so glad of it!