I'm not familiar with iRule so forgive me if I'm asking odd questions and providing bad advice:
Is the iRule page controlling the Kaleidescape system via IR or control protocol commands?
If you are controlling via IR, then the number pad can still be used to enter PINs for the various levels of Parental Control settings (if used). However, if you are controlling via control protocol commands, then you could use the number pad (and associated letters) to enable/use quick filtering, search and jump on the Movie and Music List and Collections places.
I'm obviously going to have to take a closer look at iRule.
iRule can do both (IR would be via a Global Cache box), but we're talking to it over the network. There's already an iRule module for it, so it's pretty easy. Didn't think about the parental control, but need to implement that soon, yeah.
And it looks like the Indigo home automation suite might be the *perfect* thing to use as the middle-man server between Kapp and a home theater setup to get volume to work. It's $150 for a full license and needs an OSX machine to run on, but that's what we use anyway so it might just be killer. Their remote app doesn't look nearly as good as iRule, but their server glue stuff looks good. It'll do Python or AppleScript if you need generic scripting languages, but with what it has built in and including the available generic network module as well as a Global Cache module, I think it'll be pretty easy to make it handle what you need. Sounds like global expression matching on the Kscape output right to "send this IR command here" is the level of programming you'd have to do.
--Donnie