How do you determine which workflows have used the Useful SharePoint Designer Custom Workflow Activities solution?

Jun 24, 2015 at 3:07 PM
I work with an organization that is planning a sharepoint 2013 migration. They have decided that they will NOT use the Useful SharePoint Designer Custom Workflow Activities solution.

So, we have a couple of questions:
  1. Will the workflows that have utilize these custom workflow activities stop working if we do not install the .wsp on the new SharePoint 2013 farm?
  2. Is there an easy way to determine which of the 1000 or more workflows use the custom workflow activities?