hi everyone,

I have a LG Optimus Black (P970) but I'm using this subforum and not the subforum for my phone because this a general thing, or at least the most of it.
I want to "play" with custom rom's and custom kernels. But I'm afraid because the warranty. So I have a few questions.
1. How to backup the stock rom, the stock kernel and stock recovery image?
2. How to restore this backup so that if I have to send my phone to the warranty, I wont have any problem and LG wont find out that I flashed a custom rom/kernel/recovery.
3. I saw that if I install a recovery rom and then install a custom rom, after each boot, the recovery image e flashed with the stock one (/system/recovery.img). Is this true?
4. I saw a tutorial to install the stock rom:
1. Download LG Mobile Updater ([Only registered and activated users can see links. ])
2. Install Mobile Updater
3. Remove Battery from the phone and plug it to the Computer while Holding Vol-Up Button. Display should now show S/W Upgrade
4. Start the Mobile Updater, if needed install USB-Drivers
5. In the Menu of the Mobile Updater choose Customer Service -> Emergency Repair
6. Enter the IMEI of your Phone when the Updater asks for it and click Check
7. The Phone gets now reflashed. All Partitions except the Data Partition will be reflashed.
This will install the stock rom, the stock kernel and stock recovery image? And this will be like a fail safe? For an exemple, if I brick my phone, I can always use this and revert any changes and unbrick my phone?

Thanks for all the help you can give me.