External profile not working
I just started using Zotero in earnest a few days ago. I did about an hour's worth of research in Zotero on my desktop (created some folders and subfolders, added some documents), and when I went to access it on my laptop, it would not show up in Zotero. I'm using Macs and my .mac iDisk to store the profile. The files I saved are there in the storage folder (I can see them on either computer), but only the computer that created them can use them. Is there a bug in using .mac to store a profile?
Grab MenuMeters and turn on the network monitor, and you should see the downloading and updating of data as it happens.
I'd recommend keeping the Zotero files on your hard drive and copying them to the iDisk (erasing what's there first) before you switch computers. With rsync or a good backup utility you could do this efficiently (and without erasing first) so that only modified data was transferred (including only the portion of your database that had changed).