I had trouble uploading a piccy of me initially too, so i think i know the problem !
click on upload a file from your own pictures, then somewhere further down - out of sight so i had to scroll there was an upload button, depends how big your screen font is i suppose, so u might not have to scroll down, past all the sample avatars, the button was green I think but it wasn’t called upload, it had an odd word (which didn’t seem logical to me )
anyway, hope that helps, the thing i am still having trouble working out is how old postings are, so can anyone tell me that ?