1. Yes you can, I am using Marlin-RC8BF-HICi3.zip
2. No. Print a adjustable Bearing Bracket here or a my modified one here.
3. That is the way we all started. After you get the Auto Bed Leveling down this is no longer a problem.
4. I am using the Firmware form here
5. I Have a BuildTac surface, and guess what I use a piece of Vinyl Transfer Paper to Print on.

T1.jpg

6. Original Firmware can be downloaded from here.