If you get the following message "Your SPF record requires more than 10 DNS lookups to process. This could be caused by including domains that require multiple lookups. Try simplifying your SPF record by removing any unnecessary parts." it means that your SPF is too long, and that you cannot add more to you SPF record.
You can solve this by doing following:
- Create a new subdomain in your domain. Eg: support.betternow.org/
- Under that subdomain, create a SPF TXT record
- Create an emailaddress in that subdomain, to receive Mandrill's verification email. Eg email@example.com