While I don't have a 990 (1050). I can give you my two cents worth for programming a MX-700

1) Don't put your devices on the first page, put them on the 2nd page. Save your first page for activity type Macros. Yes you can have a single macro, turn on your TV, turn on your 990, select or change the input on the TV, select the 990 mode and then go to a device page that controls the predominate functions (e.g. a DVD). Another example is to create a macro for the 990's tuner called radio. The device page it links to then has sub buttons for the 10 or 20 stations you listen to most (that are also macros). That way you don't need to tongle through a host of presets.

2) Since you give them separate names, you can have a device more then once on the 2nd page. I start out by creating one from the device remote in learning mode and then test other users device pages using a 2nd description. I have found this a great way to get non-documented descrete function codes (e.g. my toshiba HDTV does not have descrete on and off codes built into it, but they are available on remote central).

3) When writing the macros, you may find you need to add substantial amounts of delay (e.g. the TV may not accept additional signals for 2-5 seconds after powering up). I have found it useful to switch the signals between devices to minimize the delay times (e.g. turn on the tv, turn on the 990 via the device that represents cable/satelite TV, then turn on the cable, then have the tv select the cable input).