I just bought this plugin and succesfull installed it.
I configured some options and now I was ready to add services and categories.
But as soon as i click on add services or categories the popup appears and suddenly disappear again, so i'm unable to add services or categories.
I tried to register to this forum via Safari on Mac, and the button didn't work for the sign in, so i tried several times, then i changed to chrome.
On chrome works both registration to forum and login (on safari is not) so I thought it could be the same problem, i logged into my website with chrome to make a test but the problem of the popup disappearing remains.