I'm using Designer Pro X17 desktop. Trying to open a file last saved in Feb 2018.

I'm getting the message above. I saw a similar post that support helped find the shape that may have been causing the problem and removing it by opening the file with an older version X15.

I have 2 questions:

1. How do I identify the questionable smart shape?

2. How do I install an older version?

Also, I cannot seem to contact support directly. Anyone know why?