Here's the full list of act one levels, that I've been trying to assemble in the proper order. You'll note that a lot less than half of them are seen in the beta.
The working theory now, thanks to Grug for the idea, is that Act One as seen in the beta is VERY different than the final game form. It seems weird that the skeleton king is battled before you reach most of the levels about him, see the ghostly cinematic of his queen's death, etc. It's also weird that the cultists are only seen related to the templar, but not before or after. Seems like stuff is out of sequence there. And note how easily you get the 3 inventory items; not much story or ceremony attached to them. They seem ripped out of the full context/story.
That's a subject for a larger analysis, though. For now, here are the full list of act one levels, from the game code. They're listed alphabetically there; I've rearranged them into roughly their order in the beta, with other stuff below the break. And some notes. Add comments or corrections as you know them and I'll rework the sequence.
Levels as seen in the beta, in order: (Some levels are listed twice, if multiple events occur there, such as outside the tristram gates.)
A1_trOUT_NewTristramOverlook Overlook Road -- starting point. Run up to Tristram gates for next events.
A1_trOUT_NewTristram_AttackArea New Tristram
A1_trOut_Tristram_Inn The Slaughtered Calf Inn -- talk to leah, zombies attack
* A1_trOut_Tristram_LeahsRoom Leah's Room
A1_trOut_Tristram_CainsHouse Cain's House -- found in town. optional area.
A1_trOUT_NewTristram_BannerProblems New Tristram -- back to the front gate, kill zombies, wagon explodes to clear path north.
A1_trOut_Old_Tristram_Road Old Tristram Road -- road north out of town.
A1_trOut_Old_Tristram The Old Ruins
-- back to town to get Leah
A1_trOUT_Adria'sHut Adria's Hut
* A1_trOut_AdriasCellar The Hidden Cellar
A1_trOut_Old_Tristram_Road_Cath Old Tristram Road
A1_trOut_OldTristram_Cellar Musty Cellar
* A1_trOut_OldTristram_Cellar_1 Dank Cellar
* A1_trOut_OldTristram_Cellar_2 Damp Cellar
* A1_trOut_OldTristram_Cellar_3 Dark Cellar
A1_trOut_oldTristram_TreeCave Mass Grave
A1_trDun_Level01 Cathedral Level 1
A1_trDun_Cain_Intro Leoric's Passage
A1_trOUT_Graveyard Cathedral Garden
A1_trDun_Blacksmith_Cellar Cellar of the Damned
A1_trOut_TristramWilderness The Weeping Hollow
* A1_Fields_Den_UniqueMonster Den of the Fallen
* A1_Fields_Den Den of the Fallen Level 1
* A1_Fields_Den_Level02 Den of the Fallen Level 2
A1_trdun_Crypt_Special_00 Defiled Crypt
* A1_trdun_Crypt_Special_01 Defiled Crypt
* A1_trDun_Event_JarOfSouls Defiled Crypt
A1_trDun_FalseSecretPassage_01 Defiled Crypt
A1_trDun_FalseSecretPassage_02 Defiled Crypt
A1_trDun_FalseSecretPassage_03 Defiled Crypt
A1_trDun_FalseSecretPassage_04 Defiled Crypt
A1_trDun_CrownRoom Chancellor's Tomb -- get king's crown
A1_trDun_Level04 Cathedral Level 2
A1_trDun_Level05_Templar Cathedral Level 3
A1_trDun_Level06 Cathedral Level 4
A1_trDun_Level07B The Royal Crypts
A1_trDun_Level07D Crypt of the Skeleton King
Other Act One areas not seen in the beta, grouped with our current knowledge:
A1 Adventureland A1 Adventureland -- secret cow level redux?
A1_Fields_RandomDRLG_CaveA_Level01 Lost Mine Level 1
A1_Fields_RandomDRLG_CaveA_Level02 Lost Mine Level 2
A1_Fields_RandomDRLG_ScavengerDenA_Level01 Scavenger's Den Level 1
A1_Fields_RandomDRLG_ScavengerDenA_Level02 Scavenger's Den Level 2
A1_Fields_Cave_SwordOfJustice_Level01 Khazra Den
A1_Highlands_RandomDRLG_GoatmanCaveA_Level01 Cave of the Moon Clan Level 1
A1_Highlands_RandomDRLG_GoatmanCaveA_Level02 Cave of the Moon Clan Level 2
A1_Highlands_RandomDRLG_WestTower_Level01 Watch Tower Level 1
A1_Highlands_RandomDRLG_WestTower_Level02 Watch Tower Level 2
A1_trOUT_Leoric'sManor Leoric's Manor Courtyard
A1_trOut_Leoric_Manor_Int Leoric's Manor
The tinker quest leads to the mystic. You rescue her in her broken down wagon, apparently in or near the Highlands.
A1_Fields_Vendor_Tinker_Exterior Sheltered Cottage
A1_trOut_Vendor_Tinker_Room Tinker's Hovel
A1_trOut_MysticWagon Karyna's Lost Wagon
A1_trDun_Cave_Highlands_Random01_VendorRescue Highlands Cave
A1_trOUT_Highlands Southern Highlands
A1_trOUT_Highlands2 Northern Highlands
A1_trOUT_Highlands3 Leoric's Hunting Grounds
A1_trOUT_Highlands_Bridge Highlands Crossing
A1_trOut_Highlands_DunExterior_A Highlands Passage
A1_trOUT_Highlands_ServantHouse_Cellar_Vendor Abandoned Servant House
A1_trOUT_Highlands_Sub240_GoatmanGraveyard Ancient Pyre
This leads to the siegebreaker battle, as seen in the 2008 demo movie?
Maybe nephalem cube must be found in some quest dungeon? Blacksmith sends you to find it? Too easy/convenient he's just got it to hand to you.
A1_trdun_Cave_Nephalem_01 Warrior's Rest
A1_trdun_Cave_Nephalem_02 Crypt of the Ancients
A1_trdun_Cave_Nephalem_03 Drowned Temple
A1_trDun_Crypt_Event_Tower_Of_Power The Lyceum
A1_trDun_Crypt_Flooded_Memories_Level01 Decaying Crypt Level 1
A1_trDun_Crypt_Flooded_Memories_Level02 Decaying Crypt Level 2
Jail levels were in Blizzcon 2010 demo.
A1_trDun_BridleJail Cells of the Condemned
A1_trDun_Bridle_Level09 Desolate Chamber
A1_trDun_Jail_Level01 The Cursed Hold
A1_trDun_Jail_Level01_Cells The Cursed Hold
Halls of agony were in Blizzcon 2010 demo. Apparently you find the jeweler there.
A1_trDun_Leoric01 Halls of Agony Level 1
A1_trDun_Leoric02 Halls of Agony Level 2
A1_trDun_Leoric03 Halls of Agony Level 3
A1_trDun_WitherssLair_02 Chamber of Suffering
A1_trDun_WitherssLair_Jump Halls of Agony Level 5 -- withers is a code name for a known boss. Hint... was in D1.
A1_trDun_Leor_Jeweler_01 Torture Chamber
Wortham is accessed via a ferryman outside of Tristram. Won't take you there yet in the beta. It's apparently where you get the Scoundrel.
A1_trOUT_FishingVillageHeights Wortham Bluffs
A1_trOut_TownAttack_ChapelCellar Wortham Chapel Cellar
A1_trOut_Scoundrel_Event_Old_Mill Level area for scoundrel event.
a1_trOut_Scoundrel_Event_Old_Mill The Old Mill
A1_trOut_ForlornFarm Forlorn Farm
A1_trOut_BatesFarmCellar Farmer's Cellar
A1_trOut_Fields_Vendor_Curios House of Curios
A1_trOut_Fields_Vendor_Curios_Exterior Lonely Dwelling
A1_trOut_Wilderness_CorpseHouse Pillaged Home
A1_trOut_Wilderness_Sub80_FamilyTree The Rathe Family Plot
Spider queen boss ending:
a1Dun_SpiderCave_02 Lair of Araneae
A1_C6_SpiderCave_01_Entrance Caverns of Araneae
A1_C6_SpiderCave_01_Main Caverns of Araneae
A1_C6_SpiderCave_01_Queen Chamber of Queen Araneae