Mfan,
I agree with the advice that gby gave you plus his pointer to remotcentral is a good idea.
Remotecentral is just like avsforum but only for remote controls (friendly,lots of very knoweldgable people,etc.)
The one are that I may disagree is that if you you have a decent amount of HT gear, you may want to think about investing in a high end remote.
Personally, I am very biased towards the HTM line and have the MX800.
It is a hard button lcd type remote with the emhpasis on hard buttons.
You can use Pronto files in the HTM remotes and you can usually snag a great deal on an HTM on Ebay.
I think it is because a few of the models are really for custom installs and I guess the dealers get good prices on the few custom install models (MX700,800,1000) that they unload on the market.
I got both my MX700 and later, the 800 at a HUGE delta from the MSRP on Ebay.
I have an MXD file with all the features (plus some macros to simplify a few things) for the Zenith. It is part of my complete MXF file for all 10 of my variaous devices.
The one for the Zenith that was on remocentral was not so hot so I used a few items and then did the rest myself.
Have not gotten around to uploading mine to remotecentral.
On the subject of the service menu codes, I did snarf the * key out of a Pronto CCF file that I found on remotecental to use for my HTM since the HTM does not have that * key.
Sorry to go OT but:
To give you an idea of the HTM's versatility, after 9 months of owning my Nikon D70 camera, I found out that it had a remote that allowed remote firing of the shutter.
I was too cheap to spend the money on it plus I figured the HTM must be capable of doing that.
I heard that someone on remotecentral had taught (either the HTM or the Pronto as I forget now) the IR code for the NIkon D70 remote controller trigger.
As usual, I went to remotecentral, grabbed the code and now also use my MX800 to remotely fire the shutter on my camera.
A Home Theater remote being used to control a digital camera

If you have a digital camera with remote control capabilitiliy, look into the HTM as a possible alternative.