The consistency of levels whilst adding and removing abilities is inconsistent.

As an example, I start out with 3000 xp. This gives met 40 levels (and the bar is half full).

If I apply a glowing effect on me, I suddenly have 45 levels, whilst the xp has correctly gone down in the AE interface.

Now if I put the ability back in the bottle, I have 47 levels whilst xp is back to 3000.

Thanks for reporting, will look into it.