Arcane Surge actually is bugged for the door, but in the opposite way. You can pseudo infinitely stack the Arcane Surge buff on door to get increasingly bigger ability range and spirit power bonus, increasing your doors barrier on entry.
There is a pretty big bug with Doorman currently. If doorman has Arcane Surge and has Lvl2 Doorway, he can almost infinitely scale Arcane Surge's spirit bonus. This allows him to scale the spirit base of the Barrier granted by the Doorway for as many stamina bars as he has and can use. With duration items in addition, you can get extremely high spirit numbers to boost the barriers effect for the entire team to abuse. You can get enough duration to try to stack this for the entire game, although its somewhat softcapped at how fast you can scale by how fast you can regenerate stamina.