A further update to my earlier post: I submitted the Travel Authorisation I received from Immigration along with my passport details page and LOU to the Malaysian Mission in my country yesterday, and today received an email with my Travel Note. In sum, the whole process took 16 days, and I will be flying back to KL next week. I hope I have described the process concisely, and that others will be able to smoothly negotiate these bureaucratic hoops as well!