This is a guide by iwastetimeongames to how to succeed with the Angel of Light Quest. Currently you need this quest--to send the Angel of Light back to heaven in order to break many walls. She's placed a curse on the walls until she's freed. Elendil has an update that will not make it necessary for you to get this quest before being able to break those walls----but you still need to do her quest and this is a good guide.
GUIDE/SPOILER
To those who should wind up here looking for info on this, I would advise to avoid undertaking most encounters/side quests on your way to the lighthouse. Still, you will have to move up a couple things to do in order to get the Help the Angel quest that gives you an item enabling you to open fake walls in the Monastery and the other early-game locations.
1) You will have to go to Redshift University, south-west of Tmutarakan, accessible through the first teleporter in the Cave of Ascetics. (I *strongly* recommend to Mark the teleporter room.) Try to keep as straight a line as possible so not to have to interact with anyone unnecessary at the wrong time in the game.
2) Once at the University, speak with PointofLight (north-easternmost door), to get the "Repair the Lighthouse" quest.
3) Before leaving Redshift University, as PointofLight will also advise you to do, speak with Chdo, in the complext right south of PointofLight, north-westernmost door. He will give you an item that is absolutely necessary for the Lighthouse.
3a) *OPTIONAL* You may talk with everyone at RU and get their items/quests. However, mind Silvergirl (the conversation with whom will trigger some further steps along the game), Hermione (be polite to her!), and especially Old Shaman, who will give a timed quest, which though can be repeated if you are late. Especially low-level characters should avoid doing all this till a later time. (*AND* if you do undertake Old Shaman's timed quest, make sure you have the Fly Swatter, which you will have found on the floor in the Cave of Ascetics.)
4) Once you have PointofLight's quest and Chdo's item, Recall to the teleporters (or walk your way back to Tmutarakan and use the teleport to the Cave) and take the second teleporter from the left, taking you to Belovodsk. The Lighthouse is to the north-east, ideally between the potionist and herbalist's symbols on the map. On the map the entrance will look like a more 'serious' dungeon door.
5) Once inside the Lighthouse, take care of enemies (again, you need Chdo's item) and circle around the wall till you find the opening to a room where a Lady – the Angel – is. Take her quest and at this point you're good to go back to the Monastery (which you can only do either by Recalling there or going back to the Cave of the Ascetics and climbing out of it back to the Monastery garden).