Yes, SPF entry in master.cf was incorrect, glad you caught it.
The system should allow the mail regardless of case, because the domain is specified. Are you using relay recipients or look_ahead?
Also, have you followed my little writeup on how to create the domain admin and the entries for domains and transports? It's under the Baruwa section. Without that section being completed, the system won't relay messages since the relay domains aren't present.
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