if u want unlimited mana for your rogue, just have full mana and search for the value in 4 bytes. then put on/off any item that changes your amount of mana and search for the new value. when u have 2 adresses left, just freeze them and u have endless mana for your archer skills. your mana line will dissapear, but even when its gone u can still use ur skills. but be aware, this only works for the attack skills, not for minor healing, evade, safety etc. and only for rogues. i tried it for mages too and he keeps fireing his spells even when the mana is gone, but sadly they have no effect then.
use cheat engine/ even not UCE
http://cheatengine.org