Damn :0
2. Ehhh I don't know what changed, the badge in my own save is fine but I don't know what caused it in your case.
3-4. Fixed! :p
5. Ah! Well well I don't know about this but the calculation of the damage is in a percentage system, which is 2x^2/(x+y) , x=damage, y=defense, so technically... it shouldn't be negative. (I haven't tried it though, my character is just lvl 13 and I see other dudes having like lv 30 in this game :O I'll see if there's anything I can do.