Custom Logo Not Appearing In Register Plus

I referenced previous threads where admins were having this problem and tried turning off the uploads settings and using FTP to upload the image file itself. I also renamed it from fonfaq-logo.jpg to logo.jpg. I even made it into a PNG to see if that would work, and nothing. I check the path and there’s nothing obstructing it, aside from the usual WordPress security functions, which may be the cause of this problem. Does anyone have a solution to this aside from manually hacking the code so that it gets overwritten when the plugin gets upgraded?

Thanks!