There are known issues between CC2020 and the MAC Catalina OSX currently that causes Illustrator to close when using the Knit Draw Stitches tool. If Ai is crashing when you use it in CC2020, you will have to backdate your Illustrator to CC2019 in order for you to use knit until the issue can be resolved. Below are the steps to backdate to CC2019:
Open up the Creative Cloud app and make sure you are in “All Apps” on the left side
Look for Illustrator and click the "…" button next to the “Open” button
Click "Other Versions"
Look for version 23.1.1 and click Install.
You can keep CC2020 installed while you have CC2019 installed
You will have to run the DesignPro 5.1.0 installer again, so that this time it will go into CC2019.
For additional information or support, please email support@AquarioDesign.com