LP_ASUSThank you for your reply, it is a little bit disappointing that unrelated hardware issues are not covered under warranty. Will the phone be still serviced as an "Out of Warranty (OOW)" product?
You can find the complete warranty info here, but it sounds like you understand the gist of it.
As you noted, if you unlock the bootloader, your warranty is completely null and void. This would apply to software and hardware support.
If you want to test out custom ROMs, we would suggest doing this after the 12 month warranty has expired.