I cant help on this matter unfortunately but does anyone know if these types of warnings slow the site down in anyway or effect it negatively? I'm guessing warnings still arent good to have?
You can increase the max user connections through your php.ini file but this will take a toll on your server resources. I think default for shared hosting is 25 concurrent connections
Erm I'm not sure if its compatible with all themes, I did have to have a slight play with it to get it to work right
If you have a theme found on oxwall.org pm me the name of it and I'll let you know if it works or not. If it doesnt I can assist or contact the developer who is normally happy to help.