just so this is here too for others
1. no there isn't unless you get into a momentum type esc, that has those options.
2. you want the Castle CCBEC 10 amp, can be had for $20, is fine tunable down to a 1/10th, but requires castle link to do it. Comes 5.2 volts stock. There is also a couple from exceed that are not fine tunable but are switched between voltages of 5.2 or 6.0. Align offers a voltage regulator for tail servos that could work, but i'd rather see you have the bec taking care of things. Any spikes are gonna send you into terra firma. If you want it fine tuned, ship it to me first and i'll be happy to fine tune it and send it on. I have the castle link.
With the bec installed, you use your existing esc with the red wire removed from the esc connector where it plugs into your rx. the directions are on the package
3. no you can't without a lot of money in a real regulator like arizona regulators
diagrams, downloads, etc.
http://www.kdsmodel.com/downloads.asp?N_C_ID=169But, this place has guys running these and is a wealth of knowledge
http://helifreak.com/forumdisplay.php?f=180These things are finiky to setup. Requires 32 bit xp or 32 bit vista to program
I found a link to something like i was talking about but this one is futaba, i think that's what you have
http://upload.kapanlagi.com/h/20091205081932_hjbfmsetting_4b19b5249a551.JPGhttp://upload.kapanlagi.com/h/20091203082548_cable_4b17139cc1ea0.JPG