As the title says I can't uncheck 'Show auras as bars' in Widget -> Auras -> Bar mode

I managed to fix this issue by updating line 4208 from Options.lua with 'set = function(info, val) SetValueWidget(info, val) end,'

It's not easy to see, but it's a toggle between bar mode and icon mode. So, to disable bar mode, you have to enabled icon mode (Widget - Auras - Icon Mode). That should work without a fix to the Lua code.