I see that you are looking for some bug testing so I noted down some issues I noticed while testing the tool:
1- I noticed for mouseover prediction on a lvl 1 mob while being lvl 1 and with IMAWAL active, that bonus XP is indicated as 2 (as if using a Balanced Dagger; maybe related to line 89 in your code) but it should be 0. When you then kill that enemy, XP gained is correct however (1 and not 3 as indicated by prediction).
2-If I am level two and mouseover on a lvl 2 while IMAWAL is active, the bonus XP is yet again 2, when it should be 1, and killing the lvl 2 actually adds no bonus IMAWAL XP to my current tally. (i.e. Starting at 0/10, killing the lvl 2 while being a lvl 2 when IMAWAL is active should leave me at 3/10, but prediction shows it as 4/10 and actual XP after kill shows 2/10) Similar behaviour is observed at higher player lvl equal lvl kills.
To further add to your headaches (
