i selected the photos 72.5mb only ,typed in a tag and description. visibility is public. rights is CC-attribution. geotag is checked. synth button is greyed out. can't create synth. i'm new here so i probably did something wrong. please help.

nevermind. i figured it out. needed to give at least one photo a name.

Actually it's the name of the entire album, but you're right. You need to have at least three photos and a title for the synth.

Ahh, a day and a half of irritation, only to find out I,m a retard. Yes people if you have the same problem just fill out the very first blank field (name the photosynth youre uploading) and like magic everything works.