Compliance Checklist Question Attachment

We have enabled the Compliance Checklist functionality in our test environment and I have set up a template with the applicable questions. One of the questions requires that an attachment be uploaded. When I click the button to add the attachment, the attachment popup window appears for a second from the right side of the screen and then disappears. If you click the Add Attachment button again, nothing happens. I'm not able to add the required attachment to the question. Since the attachment is required, I cannot validate nor complete my checklist.