As far as macros, the first time I did one of these I sat down with the remotes and planned out one activity at a time. I would physically use the remotes - from everything powered off - and write down every keypress I did until I had it down. I did the same thing for every activity from power off. Next I did the same thing from a "changing what I was watching" perspective (going from watching DVD to watching another source - like TiVo), until I had all my "change" macros down. I also put together a "Power Down" macro in the same fashion.

After that I programmed it, noted what commands went unresponded to and made sure that the individual command actually worked (sometimes this requires a temporary page with individual commands for testing). If not, I relearned the command and tried again. If the command actually worked then you probably need a delay in there to have the command wait until the device is ready to receive a command.

Last I would sit down with my device and figure out what commands I would actually use from the original remote and discard the rest.

After that you are done other than aesthetics - which always need tweking as you find new graphics, etc. Don't get discouraged, it takes a while to get the ball rolling the first time, but when it does, it rolls VERY well