Twine 2.0/Harlowe Images and Dropbox

I have a story in Twine 2.0/Harlowe that makes use of many images. As a test run, I put images in Dropbox and referenced them with proper addresses and such. They show up in the story fine... as long as it's on the desktop used to link them, and nowhere else. I'm working in browser, so I can get them to show whether it's Chrome or Firefox.

I need to get these images visible on someone else's machine, not just mine, without a lot of work.

But if I Publish to File, copy to flash drive, and hand the flash drive off to someone else, the links break. This happens even if the second computer is the owner of the Dropbox folder where the images are stored... they definitely have permission. And the breakage also happens if I use a second computer and can sign into Dropbox using my account.

The only solution seems to be to open up the Twine file editor, once for every new computer, and manually recopy every single link. This is an effective workaround, but clearly an impractical one. My audience is strictly internal/co-workers at the moment, with whom I can share Dropbox access, but I'm not telling my readers/players that they must paste in all the art addresses.

Other potential solutions I see but might waste my time:
* Web hosting of the images rather than Dropbox
* Saving all images to flash drive and praying the file extension remains the same when slotted into a new machine

There's got to be an easier way... what am I missing?

Thanks in advance.