Is there a way to attach a file

You can create a new property definition of type "Choose from list Documents" and add this to your template. This would let the user find a document in M-Files and add a reference to it on the metadata card. You can add a filter to the property definition if you only want to see, for instance, documents of a specific class in this property.

Then in your workflow state, you can add a post-condition "<property> is not empty" which would prevent the user from moving forward in the workflow before some document has been selected in the property.

Thanks Joonas. You are a Star