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0. I have a lot of blocks with zeros in the SkillPrerequisits block; they need to be removed. You have two of them.

1-2. Go to GameMechanics/Creatures/Creature/Race/Creature Name.xdb. Copy the same folder structure and the file itself; in the file, find the Abilities block and add the same abilities as the other one... or better, check out this guide; it shows how to change a creature.
https://youtu.be/N1L52c2MSU8

3. Mods with the .pak extension are placed only in /data/, mods with the .h5u extension are placed in UserMODs. Mods with the .h5c extension are placed in UserCampaigns, and mods with the .h5m extension are placed in Maps.

The difference is that the editor can see .pak mods. The others cannot. And yes, don't give your data folder a name. To avoid conflicts.