[BUG] Summit Event Registrations created from "New" button in Salesforce don't have needed validation

[Scarrien]

If a Salesforce user adds or edits a new Summit Event Registration record from within Salesforce, there isn't validation on the page layout to ensure the record is created correctly. This results in null pointer exceptions in triggers in our package and missing data relationships.

Specific problems

• Instance field needs to go before Event on layout
• Event must be required on page layout