error 0 while removing asset

While attempting to remove this asset (a test run from an uploader I'm managing), I got a Curriki Error 0

Here's the URL: http://www.curriki.org/xwiki/bin/view/GWT/Editor?xpage=plain&page=Coll_kingwilliamluke.ApBioIIChapter18Lesson6

Error text is visible in attached screenshot

NOTE: I originally got hte error several times in a row and could not remove the asset. I just went back again to re-create and grab the full error text, and was able to remove the asset without an error.