Two quest weren't getting added: Convert the ladder to a step ladder, and collect the barrels and crates to climb onto the roof.
Since all quests are required for completion and these were never getting added it was impossible to complete the game.
The quests should get added retroactively:
If you have any barrels or crates (item) in your inventory you'll get the quest for collecting them. If you have all 10 barrels and crates (item) it should complete (might require a quit to main menu and reload).
If you have a ladder or step ladder in your inventory the convert quest should be added and it'll will be completed if you have the step ladder.