1) The IRMan is just a receiver. You'll need to generate your own codes or use a remote that you don't actually use for the IR codes.
2) Yep.
3) This is harder....but can be done.
4) I think it's basically easy to use, but if you don't have a lot of experience with setting up your CCFs, you might find it a bit daunting.
5) From your questions, I'd actually recommend an IR keyboard. There are some that work well for around $40US (and others that are much more expensive...)
You may also want to check out the Girder website:
http://www.girder.nland these threads at the AVSForums:
[Link: avsforum.com][Link: avsforum.com]What you are looking to do can be done, but it is not merely a day-long project. Good luck!
Best,
Brad