Merci à toi srocher et à ceux qui t'on aidé.
Cerise sur le gâteau : fonctionne avec UltimaHacks !!! (testé que quelques minutes pour l'instant)
Jeux acheté à sa sortie et jamais fini dû aux aléas de la vie et surtout mon niveau nul en anglais.
Je pense que l'on me verra pas beaucoup les jours à venir.
J'espère que la traduction d'Ultima underworld 2 est dans tes cartons.

For posterity, I've uploaded the code and build of v0.2 to Github (forked from krokots' repository, which was empty, to give proper credit).

I've also had a little bug regarding some local teleporters. When I clicked them, I would get a NullReferenceException. I tracked down the bug and made a quick fix, so I took the liberty of publishing a v0.2.1 on my repo too.

https://github.com/KarlClinckspoor/UltimaUnderworldEditorUnity/releases/tag/0.2.1

Regarding support for UW2, it's a ton of work. But at least I tested the decompressed lev.ark from hankmorgan's editor and it's loaded properly in UW2 (only a quick test, not a full playthrough), so at least the compression/decompression aspect is solved - only decompress and work with that. Lots of hardcoded constants will need to be changed.

Adding randomizer support is even further off. I've been working on zoning (which the editor calls sectors), and now I'm revising all the zones I've created. After that, the item placement logic will have to be figured out. I've thought of quite a few algorithms, but there's always some edge case or detail that I fail to consider and need to revisit some aspects. So far, no coding, only thinking.

Nice! Thanks for the input and good luck if you ever try to update it for UW2. It's gonna be a bit of work, but it's definitely doable.