a couple of questions about making a custom ROM

[mlevin77]

A few questions about ROM cooking:

1) Putting a piece of software into the ROM - does it save memory over installing it later or does it not matter whether it's in ROM or installed in memory afterward?

2) If I have an activation code for a program I bought, can I put it into the ROM and have it be fully activated after flashing, or will I have to enter the code the first time I run it?

3) do I give up some of the speed and guaranteed stability of the
well-tested clean ROMs by shoving 3rd-party software in there? Am I better
off leaving things to be installed afterwards (but assuming I need those
apps anyway, and don't have the choice of deciding not to install them)?

4) If applications are in ROM, will I still be able to set their preferences? Is that done before, in the ROM cooking, or must it be done after, when the device first boots?

5) can system settings (the way I like the XV6700 set up) be specified in
the ROM?

Thanks,

Mike