How to Include the record with selected data form on a custom email alert notification?

The checkbox option to include a copy of the record disappears when I select message type custom from the email contents section of an email notification.  How do I do this?  I have a form created for it and the form is selected.  It works fine if I select default, but the problem with default is that it also brings in a list of other unrelated formula field values changes and do not relate to the recipient of the email.  I'm attempting to select custom to work around that, but now I'm losing the ability (the checkbox) to use the form to display the record.  The Data form field for selecting the form to use when including a copy of bus units still displays, but the checkbox to use it is gone.  Are there any solutions or workarounds for this scenario?  

Thank you

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Tamara Billings
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