No, there is no back door. All quests related to Mae'Var are disgusting for a good aligned party (or rather, for a good aligned player). The only "back door" is that you need not show more violence than it is needed:
1. The first Mae'Var's quest: Come at night and steal the amulet from the table (the chest). Note that Mae'Var has hinted that the amulet will be there during nights.
2. The first Edwin's quest: You must kill. No other way.
3. The second Edwin's quest: You can do it without violence if your CHA is enough high and if your protagonist is a female. Perhaps, also WIS or INT has to be high as well? I don't know. Give your protagonist the Ring of Human Influence and the Nymph's Cloak. Have some potions ready and try. You should be able to detect the nonviolent option from the menus...
4. The second Mae'Var's quest: You can do it peacefully. Again, perhaps CHA and WIS or INT might be needed. I am not sure, my protagonist is always well generated
At any rate, do the whole quest. You get a considerable amount of money and XP from Renald and some useful items.
Notes:
1. If you plan to side with Bodhi then you must do the quest BEFORE you accept Bodhi's offer.
2. At the end of the quest, you will lose Gorth's shop. Steal all useful items there before the end of the quest. Otherwise, all Gorth's goods are lost for you.