If you use Flame Walk to go through a doorway or near architecture with collision at ceiling height from where you are standing, Sienna gets stuck in a wall when using Fire Walk every time. Since you’re technically still mid-air rather than standing on anything, you cannot activate Flame Walk again, and are forced to either die or leave the lobby.
This was not a problem when Flame Walk instantly teleported, but seems to have resulted from attempts to fix how 2.0 Flame Walk initially worked.
Empire - building where the basement tunnel with a gunpowder barrel exits. Flame Walk from the bottom of the 2nd floor stairs through the doorway to the main street, get stuck in the wall above the doorway.
Empire - Building up the stairs and to the left of grim 1 building, small room with no ceiling next to roof stairs. Flame Walk from small room to hallway, get stuck in wall above doorway.
Nest - Scaffolding leading to grim 1, Flame Walk along ground underneath scaffolding, get stuck in beams under walkway.
Garden - Stairs leading down to crypt tunnels, Flame Walk from top of stairs toward bottom of stairs, get stuck in wall above stairs.