In a local install of Cypress v4.0.2, I am encountering a 500 error when opening a c1 Sample test for CMS105v7. I can create the Product successfully and access c1+c3 and c2+c3 tests. I only get the 500 error when clicking any of the c1 sample tests. I've attached an excerpt from the production log around the 500 error. 

For what it's worth, I was able to successfully create a c1 sample test and access the information on the Cypress Demo Server.