libcurl is a library Muse uses for internet connections. I expect there's something unusual about your internet connection or perhaps anti-malware/anti-virus is preventing an internet connection in an unusual way. I expect you'll be able to open the files if you temporarily disconnect from the internet before opening, but you may then crash later after reconnecting to the internet when attempting FTP upload, sync of In-Browser Editing changes, or some other internet contact.
Please send a message to muse-support@adobe.com with a link to this forum thread for context and I'll reply and attach a file you can put in your "Documents" folder to cause increased logging of libcurl activity to the MuseLog.txt file. That will provide us a much better idea what step in the process is crashing. Thanks.