If you are testing Soapbox Events and notice that your Leads are coming in and converting fine, but the resulting Opportunity record does not use the Soapbox Registration Record Type, and you didn't intentionally setup a workflow to change this behavior, then chances are good there's a hidden checkbox you need to enable:
1) Login to your Salesforce account and navigate to Setup > App Setup > Customize > Leads > Settings
2) Make sure the "Require Validation for Converted Leads" option is checked (formerly labeled "Enforce Validation and Triggers from Lead Convert"). If this is not selected, the Soapbox Engage triggers will not be able to fire correctly.
Note: If you do not see a checkbox for "Require Validation for Converted Leads" (formerly labeled as "Enforce Validation and Triggers from Lead Convert") in your Lead Settings, it may be because your Salesforce account was created before this option was released in 2008. If that's the case, please submit a case to the Salesforce support team to enable this setting in your account as noted in their official documentation here.
You may also need to do this if you experience the error message below while trying to convert a Soapbox Donation or Registration:
Error: Invalid Data.
Review all error messages below to correct your data.
Apex trigger sbxd.sbx_DonationsCampaignMember caused an unexpected exception, contact your administrator: sbxd.sbx_DonationsCampaignMember: execution of AfterInsert caused by: System.DmlException: ConvertLead failed. First exception on row 0; first error: CANNOT_INSERT_UPDATE_ACTIVATE_ENTITY, sbxd.sbx_DonationsLead: execution of AfterUpdate caused by: System.SObjectException: Field Id is not editable (sbxd): : (sbxd)