Morroblivion 0.64 Bug Report
The voyage to Cyrodiil from Seyda Neen doesn't actually elapse 3 days. The in-game time is the same as when you depart.
The "Plaza" fast travel locations in Vivec don't actually take you to the canton plazas (topmost levels) but instead the ground levels.
When NPCs have to get out of a bed that's right next to a wall, they will sometimes get up on the wrong side of the bed and clip through the wall, where they'll remain stuck.
Ancestor ghosts and Dwarven specters can be seen carrying around the shape of their remains (the conical pile of ectoplasm) even before they're killed.
When trading with the Mudcrab Merchant, the screen jumps backward slightly every time you make a transaction. He can also wander into the water and actually drown if he stays in the water. His barter option will disappear shortly before 8 PM, unlike the Creeper. Finally, he will attempt to equip the weapons and apparel you sell him, which causes a graphical glitch where his model will spread all over the water on subsequent visits.
In the ships at port town docks, many containers are inaccessible, such as the ones in the roped-in areas under the stairs and stacked behind the rails beside the interior hatch doors.
Stairways like the ones in buildings in Raven Rock have invisible walls on the sides, even though you should be able to walk under them from the side.
"The Mating Kagouti" can't be finished if you speak to Edras Orvil and offer to turn him invisible, leave for a while (I had to go acquire such a spell) and then come back. The dialogue option never comes back up with him. The only way I could finish the quest was to punch him and chase him back towards Thoronor.
The eastern fast travel point for Assarnud (the dungeon east of Gnisis) is glitched, as you will arrive stuck inside a stone and unable to get out without TCL or fast traveling to a nearby location.
The quest entry for "Fjol the Outlaw" never gets completed properly even after Fjol is killed, so it stays in the active quests tab.
When you do the quest "A Man and His Guar" with Teris Ralderan and escort him to the Vivec Foreign Quarter, he speaks to you once you reach the bridge, saying that his guar Rollie can't follow. However, if you continue to escort him to Aggrippina's store, Rollie will still follow you until you enter the waistworks door.
The Shrine of the Mask in the Gnisis temple does not function properly during the Pilgrimage of the Seven Graces. The potion of cure common disease is not needed to open the column and activate the true ash mask. If you have the potion and sacrifice it, the column opens but the true ash mask disappears.
The Ald-Ruhn Guild of Mages has too few beds. Every evening, 4-5 guild members will all try to pile on to the same bunk bed after it's already occupied.
When interacting with the Bitter Cup, picking it up has the same effect as drinking from it. Even if you don't want to drink from it, you still have your highest stat raised and your lowest stat lowered. Strangely, the altered stats will reset to normal in a few game days.
In Vos, Thilse Aralas's Farmhouse, and places with a similar layout, the second floor room is disconnected from the rest of the building structure, and you can see out into the void.
The Caldera Slave Key cannot be used to free the slaves in the Caldera Ebony Mine unless you get the Redoran quest to do so.
The Abebaal Slave Key cannot be used to free the slaves in the Abebaal Egg Mine.
In the Hawkmoth Legion Fort, if you speak with any NPC, the option "Get Me Out" comes up and they will respond as if they're a prisoner. If you've stolen the cell block key, you can even agree to free them, which makes no sense.
In Hawkmoth Legion Fort, Frald the White will sleep in the locked prisoner's cell, even during daylight hours.
When exploring the lowermost level of Berandas, Ama Nin will almost always be dead by the time you get there, since she will drop off the ledge to attack the daedra below. Since she is unarmed and has just sustained a fall, this will likely kill her, making it impossible to speak with her and give her a scroll of Divine Intervention.
Fortifying your Resist Disease over 100% will make you susceptible to disease.
In the Salven Ancestral Tomb, the vampire Mastrius will start fighting and killing the other enemies in the tomb, even though they're supposed to be his minions.
Some weapon damage ratings are off. For example, the daedric dai-katana is supposed to do 36% more damage than a daedric katana, but it actually does 4 pts less.
If you return the Hair Shirt of St. Aralor to Uvoo Llaren, wait 24 hours, and come back, she will start casting a healing spell on herself repeatedly. This shouldn't be caused by her equipping said artifact, since it's cast on use, not constant effect, and it doesn't appear on her. A few hours later you'll get the message that Uvoo Llaren is unconscious.
"Threads of the Webspinner: Fleetness" can't be completed if you get this specific quest before "Threads of the Webspinner" under Special Duties, as your journal does not update when you kill Hrordis or search her, and you can't turn the item in to Eno Hlaalu. Also, the Ring of Sanguine Sublime Wisdom can't be turned in to Eno Hlaalu until you get the specific quest for it under Special Duties.
For the Morag Tong quest "Writ for Ethal Seloth and Idrosal Vendu" the former has a quest marker but the latter does not.
If you have already killed Mathyn Bemis and Brilnosu Llarys prior to getting the writs to execute them, you'll get credit for the contracts, but then you won't be able to receive any other writs and you can't advance the Morag Tong questline. This is due to the quest for Brilnosu Llarys never showing up in your journal, which means it can never be counted as completed. Quest ID is [0100B839] and you have to setstage 100 to complete it. You can then get all subsequent writs normally.
Redoran Quest Bugs:
In the "Shishi Report" quest for House Redoran, if you've already been to the dungeon, the Redoran soldiers you're supposed to meet may have been killed and their bodies vanished. Quest ID  and you have to setstage 30 and then player.additem 011801cb 1 to get the report.
In the "Duel of Honor" quest for House Redoran, when you enter the Arena Pit to watch the duel, the two combatants will glitch out and teleport around as the fight goes on.
For House Redoran when you get the construction contract for your stronghold, the contract itself still says "PCName" instead of your actual name.
For the Redoran quest "Find Fedris Tharen" you're supposed to be able to cure him with a spell, but casting a Cure Disease spell like Rilm's Gift on him has no effect. The only way to complete the quest is to report back to Lloros Sarano.
If you visited Andasreth and explored the inside at any time prior to the Redoran quest "Recover Shields from Andasreth" the bodies of the Redoran soldiers will have vanished. Unless you collected the shields ahead of time and kept them, it will be impossible to finish the quest. ID is [01004A5C] and you have to setstage 100.
Main Quest Bugs:
In Morrowind it was possible to bypass the Fourth and Fifth trials of the main quest if you were higher than lvl 20 and had at least 50 reputation; or if you had completed the Tribunal main quest. That is not the case here.
For "Meet Vivec" after you've been named Hortator by all three houses, and Nerevarine by all four Ashlander tribes, Danso Indules will still not acknowledge the fact or arrange a meeting for you with Archcanon Saryoni. She will claim that you haven't been named Nerevarine by the four tribes. Even if you bring the tokens they gave you, it does not change her response. If you break into Saryoni's room and try speaking with him directly, there are no dialogue options to advance the quest. The quest ID is [01002C51] and you have to setstage 30 to be able to speak to Vivec. However, you still have to pickpocket the keys off Saryoni. You can still go the alternate route (that involves permanent health loss mind you) if you pickpocket the keys, break into the Palace of Vivec, then pickpocket the Unique Dwemer Artifact off Vivec.
After you retrieve Sunder and Keening, the quest "The Citadels of the Sixth House" counts as completed and all the quest markers disappear, even though you have not yet defeated Dagoth Ur himself.
Dagoth Ur's taunts as you explore his facility are not voiced. His initial greeting plays normally though, as do his voiced lines. Dagoth Ur is also supposed to deliver one more line as you enter the chamber of Akulakhan, but it doesn't play. His desperate pleas as you strike the heart do not play either.
Bloodmoon General Glitches:
(I already posted Bloodmoon quest bugs in another topic.)
The plague wolves on Solstheim are supposed to drop wolf pelts, but instead they drop the "red wolf pelt" item, which has no alchemical properties and is categorized as a misc item worth 10 gold.
The text in books and scrolls exclusive to Solstheim is formatted incorrectly, with the <BR> still visible wherever there should be a line break.
In the dungeon Skygge on Solstheim, the skeletal enemies are already killed, seemingly by the necromancers they're supposed to be allied with.