I've just installed Omeka locally on my Mac running Snow Leopard and Xampp. I added the Dropbox plug-in and batch uploaded 160 image files. I installed the CSV plug-in and uploaded the associated Dublin Core metadata for those files. But, I am unable to link them together, so I suspect I missed something somewhere. How do I do this?
You're not really missing anything, there isn't an easy way to link Dropbox files with metadata saved in a CSV file that you're trying to import.
To import metadata together with files using CSV, your files need a permanent URL, and you can import the files via the URL.
Since you have already imported files into your Omeka, you may want to try adding the file URLs to a column in the CSV titled "Files" (or "File 1," "File2," et al if you have multiple files per item). You will be re-importing those images, but then they will be linked with their metadata. I've only tried this with an Omeka installation that is on a web server, so I'm not sure if this works with local installations.
Then you can delete those items that you created by batch imported all of those images.
Alternatively, you can add those files to the Dropbox again and leave them there. Import your CSV file and create the items and metadata. Then go in and edit each item and associate each file sitting the Dropbox folder with the item. http://omeka.org/codex/Plugins/Dropbox
I tried adding the urls to the csv file, but I didn't really know what the url on my local installation should be, so this could have been the problem. Once I get going, and have a server set up properly I'll try that approach. Your second suggestion looks like it will work, although I hit another snag due to invalid mime types, which I haven't fixed yet. If you can point me to correcting that problem, I'd surely appreciate it.
Try disabling file validation, in the Security Settings section of the /admin: http://omeka.org/codex/Managing_Security_Settings
Ahhhh, success! Now for the next question:
My image files are rectangular, but the thumbnails seem to be square. I see in the archive folder that there are rectangular thumbnails that I would rather use. Is there a way to default to them?
It's just pulling the square_thumbnails. Hunt around in the forums, there are a few posts that deal with this.