I go to validator site:
https://cypressvalidator.healthit.gov/

After selecting the QRDA 1 file to validate, and answer all the prompts (2015 bundle, None, QRDA Cat 1, PHI Confiration), I click Submit and get the following message (in Chrome):

The cypressvalidator.healthit.gov page isn’t working
cypressvalidator.healthit.gov is currently unable to handle this request.
HTTP ERROR 500

and shows this URL:
https://cypressvalidator.healthit.gov/uploads

I've tried with Google Chrome and MS IE - same behavior.
I tried sending the .XML file or a .ZIP file, no difference.