https://bugs.winehq.org/show_bug.cgi?id=38930
--- Comment #4 from winetest@luukku.com --- (In reply to winetest from comment #3)
I just tested another betfair bug with clean prefix and no overrides used, I was able to create an account and login. This is either fixed or the poker client has been changed too much to replicate the bug.
wine-1.9.16-145-gdca0e38
To make sure I even used winetricks and set all dlls as builtin. I am still seeing loging window and able to login after this.