The popup error containing the text "'Save to file failed. A device attached to the system is not functioning.'" as well as the name and location of your file refers to a network connection issue (we have most often seen this for users in the Blackbaud hosted environment).
Unfortunately, it's not something we can fix as it means that it could not find the link from hosting back to your machine. We believe that it is due to a temporary glitch in the network connection rather than anything more sinister, but the error is generated from RE itself and not Importacular.