The old Alcugs list has been migrated to GoW, so you should be good Aloys.
ametist, welcome back! We declared that part of the list as "not editable" because, at least for some time, it was managed in parallel by the ULM (Uru Library Manager) database. As far as I know, that database is dead. We still don't reserve new prefixes in the ULM range (there's enough free space around it), but making use of your already existing reservations in that range is fine.
(Übrigens spreche ich auch deutsch, falls dir das lieber ist.
)