This tutorial for magic upscale is specifically for Reunion mod, though i hope it may be of some use to you. While using Reunion mod, this is what i do in order to get them to work correctly with reunion:
Magic textures will be read from "New_Translation" folder, and inside it, there is a "textures" folder, that's where you put "battle" and "magic" folders which are the textures you need. All of the rain, seffect, etc pngs have to be in battle folder, and a lot of subfolders (like limit, summon, spell) with a lot of pngs have to be inside "magic" folder in order to work.
(eg. rain7_00, seffect1_00)
/->battle (folder with 82 pngs)
so... it should be like this: The_Reunion -> BASE -> New_Translation -> texture ->
/->magic (folder with 8 subfolders and 1299 pngs)
(e.g: blue, limit, summon) (e.g: a1_00, a2_00)
Hope it helped. Do note, that magic textures provide some microstutters during casts, at least that's what it did for me, so you'll have 1-2 seconds freeze whenever you cast a heavy spell, especially summons.
As DLPB stated, enabling texture compression in Options.ini seem to alleviate the stuttering problem, though not completely fix it as heavy stutters seem to be present once, on the first load, after the area completely loads, stutter will be no longer present until you reach a new area.
Hope it helped
Edit: Oh, i didn't notice you were actually looking for help with Reunion. Then i guess, this will help you 100% since it works for me no problem.
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