There is a full webinar, including Q&A after that, all told, includes several hours of discussion about reverse mortgages (RM).
Those videos can be found on the Webinars page. The webinar title on that page is: "The Pros and Cons of Reverse Mortgages."
The full webinar will explain the concepts and facts related to the various kinds of reverse mortgages, risks and advantages.
In the main webinar video, Kotlikoff's discussion of the RM begins at the 58:00 min mark. In this discussion he points out that the key thing for modeling the RM in MaxiFi is to note that there is "money in, and money out." You use an Alternative Profile to enter a nominal special receipt (lump sum) or receipts (receiving the RM payments like an annuity) to represent this money in. The money you are going to be paying (i.e., money out) is set up like a special expense. If you plan to stay in your home until the end of life, you enter this nominal special expense in the last year of the model.