In Firefox 45 it throws up an error dialog right off the bat (edit: coming from Harlowe), then seems to start normally. In Opera 45 it seems to work, but predictably enough without audio. Hope this helps.
Thank you! I can't say I am able to replicate those errors (I've tested exclusively in Firefox from the beginning and never ran into an error dialog), but at least now I know FF is not a given.
