Do you have cookie support disabled in your browser?
The session id is stored in a cookie, which gets validated if you want to access the image files. So not authenticated users can not get access to your images.
Disabling Cookie Support would lead to that issue.
The graphics are updated every 15 minutes (0/15/30/45).
For a new install, this means the graphics will be missing until the system clock shows a full quarter.
So if the first bootup finishes XX:59:59, the graphics will be there instantly. If it finishes XX:00:01 you have to wait 14 minutes and 59 seconds for them to show up.
The password/SSH stuff is probably unrelated. [:)]