Best Practices for Validating a specific step in a wizard


In step 4 of our wizard (creates and updates Leads), we have 12 integer fields… at least 6 of them must have a value greater than 0 (and must not be null) before the user can proceed to the next step.  

What are the best ways within SQUID to handle this?  We tried standard Salesforce Validation Rules but that would only work if we could specify what step we are on in the wizard on the Lead Record itself. 

Thoughts?  Ideas? 

we have something similar in a custom snippet that checks for meeting the necessary criteria when clicking a button.  we just added the “Run a Skuid JavaScript snippet” action type as an action that occurs before saving the model changes.  But, I’m also looking to see if there is a better way to do this.

Also, i just found this page with a section called “Example: Validate required fields on Models, then navigate to another step”: