I've been working on a website on two different computers, one at work, one at home. The files are on my local Dropbox folder on both computers. On each computer the assets show up fine, although I had to relink them on the home computer even though they're in the same Dropbox folder. Now, when I export the HTML at work, everything's fine, but when I do the same at home, the images folder is empty without warning, even though in the assets window, everything is accounted for. Bug?
That seems to be a different problem.
Once placed, Muse doesn’t need the original assets any more, because they are kept within the .muse file.
That means: Muse exports your assets correctly, even if these data aren’t available and the "Assets" panel shows the red question mark.