Dear Dan,
If you custom field is called restricted, you need to add the wpcf- prefix to evaluate:
Change 'yes' to whatever value you store in the custom field.
[wpv-if field="wpcf-restricted" evaluate="$field = 'yes' AND '[wpv-current-user info="role"]' = 'administrator'"] Only administrators can see this [/wpv-if]
Please let me know if you are satisfied with my answer and if I can help you with any other questions you might have.
Regards,
Caridad