I can read about a lot of problems around the internet ...
Yes gapan, I should not use it then
This is the oppinion of the author, it does not force you to share and is signed automatically.
You are free to keep them all errors for your own. Linux is the best game I ever played.
Afaik it's supported. The only problem could be the limited size of the core image, because only 62 sectors are available for embedding.
I think the safest approach would be puting /boot/grub onto a non-LVM device, so grub2 mustn't use LVM drivers to load itself instead it can load the drivers like the grub.cfg from your partition to access your LVM volumes.
However, to my knowledge LVM is supposed to be supported and size problems only arise when using LVM as well as RAID. But I never really tested it myself. I recommend you experiment a bit with different setups in a VM.