I can explain this. We set up the system so that people must reach the "active member" level before posting pictures. It is really easy to become an active member -- you automatically reach this level after only 10 days and 5 posts.
Until recently we had a bug where people who weren't active members could still add a picture in the edit window after creating a post. That was fixed yesterday.
I am very sorry for the inconvenience, but this is one way that we combat spammers.
Mo and teri, clearly you aren't spammers and it is great to have you on YLF. If I had a way to push you to active member status early I would, but unfortunately I don't have a mechanism for doing that. I hope you'll stick with us for a few more days.