I saw your question here, good evening in advance... Regarding the problem, it's not exactly a problem but rather the methodology the system uses for buffing.
The level of the buffer inserted into the character ends up being higher in level than the buffer you are trying to insert.
The same thing happens if you buff the CB (community board), then the buffer of the character's skills, and finally when you use the GM buffers; after you buff them, you can't buff any more because they are stronger than the CB's and the player's.
I don't know if it could be classified as a bug, since it's only inserting the buffer, but it follows the following logic to define the strongest one: Level > Power > Time.
I hope this helps. I'm also having problems with buffers, specifically with IDs, where we have several repeated IDs for the same skill schema. However, the icons and effects are based on characters when buffed using Alt+K, using the correct effects and icons for that character. This ends up breaking the "custom buffer," which only shows: The effect was applied" " when buffed, where the buffer name should be instead of quotation marks.
If you find a solution, I'd be happy to know and share it as well.
Thanks!!