As mentioned in the Spell Lists page, Spell Lists are intended to be for NPCs what Progressions are for Players - as such, I don't really recommend setting real Progressions for NPCs - this mutator is primarily intended to wipe progressions from NPCs by replacing them with useless ones, letting Lab take care of everything a progression would normally handle. Still, you can do what you want, it's your game.

You add progressions by looking up the Name associated with a TableUUID - as TableUUIDs are arbitrary values with no backed resource, this is programmatically derived by Lab, using the first Name node asssociated to a progression with a given table id (so it may not be exactly what you think it is, especially with poorly modded/wackily designed progressions).

Progressions can be set to a % of the character's level - these values do not have to add up to 100%, they are completely independent of each other, representing class/subclass/race/whatever progressions. They aren't directly tied to Spell Lists either, per the initial reasoning above, but you can conditionally apply a Progression group to an entity based on whether or not they've been assigned a certain number of specific lists, if you want to ensure your progressions adhere to the entity's assigned Archetype.

• Progressions are one of the weirder components in the game - they aren't simple properties on an entity, they're actually entities in of themselves, associated to an entity via the Owner component. To prevent compounding bloat, Lab will destroy any progression entities it removes from a character entity, recreating them as necessary. I haven't seen any adverse impacts from doing this.

[DEBUG] (S) ==== Starting mutator Progressions (priority 10) ====
[DEBUG] (S) 1 potential progression groups were identified - randomly choosing one
[DEBUG] (S) Assigned progression de43ebc2-241f-4d98-9937-b8858a016d8f at level 1
[DEBUG] (S) Assigned progression ada873bb-ba54-40f2-b983-9db19f85274d at level 2
[DEBUG] (S) Assigned progression 87ce1f36-a954-4147-aaf8-69bd855ab48f at level 3
[DEBUG] (S) Assigned progression b639647e-1e93-44f7-ac34-3d8d07a1c094 at level 4
[DEBUG] (S) Assigned progression 469bc52a-6f2b-4f93-9d8f-5032afd2c700 at level 5
[DEBUG] (S) Assigned progression 398f9ef7-fa4a-4edf-98f6-38e93ad4cb60 at level 6
[DEBUG] (S) Assigned progression 44a6c6b2-25f1-4248-82e3-3676bfe992a0 at level 1
[DEBUG] (S) Assigned progression 80f2f343-fc7a-4346-924b-b119e3354da5 at level 2
[DEBUG] (S) Assigned progression 45cf151d-5ed6-4b87-835b-6de2cec7601a at level 3
[DEBUG] (S) Assigned progression 0ae478d4-6073-47dd-975d-74871b3058a1 at level 1
[DEBUG] (S) Assigned progression 8a8e3467-05fc-4b83-8b85-5a7cf4a3d218 at level 2
[DEBUG] (S) Assigned progression db853652-779f-4c9e-a100-521bc4a5d8c9 at level 3
[DEBUG] (S) Assigned progression fe7d2be7-a48e-4b4c-b8bb-5fad54861fdc at level 4
[DEBUG] (S) Assigned progression acb38a9e-6f02-4c16-8bc8-8f6965327e68 at level 5
[DEBUG] (S) Assigned progression 96a229e6-86ef-4be3-b0a7-e36d7b2f231d at level 6
[DEBUG] (S) ==== Finished mutator Progressions in 16ms ====