I'll see about fixing this soon. Try toggling it a few times, that should fix it (it did for me).
I need more information on what exactly is happening if you want me to help.
Make sure that you're using x86 (32-bit) WoW, that OLoader has the same or higher privileges than WoW (i.e, if WoW is admin then OLoader must be admin), and that the WoW process is still valid when you click inject.