check box list block

I am building a course in Rise and there is a lesson that I had used an attachment block. We had some testers experience a problem with the attachment. The pdf did not always fully open. Please see attachments. I would like to know if anyone else experienced this problem and if anyone knows why this happens to some users.

As a work around I did a layout of all the information text contained in the pdf.  The file was a pdf that they wanted people to read and after downloading it, click something to indicated that they had read it and agreed to the terms in the pdf. like a signature indicating agreement. So I used a checkbox list block followed by a the divider "continue" block, in an attempt to simulate this request. It works to the degree that they cannot continue the course unless they click the checkbox. Can you tell me if Articulate has considered building a signature block that tells the LMS that the learner signed the agreement?