Question about screen rotation, GRUB2, and ISO build

[BrokenE39]

After getting much appreciated help in building the kernel, I got it copied into the Android folder and it boots up with WiFi and touch support. However, now I have some more questions:

1. Touchscreen doesn't work when GRUB2 menu is loaded and my volume up / down & power button doesn't do anything in this menu. What alternatives does the forum suggest I use to support dual boot? I also tried iReboot but it doesn't detect the Android install (NTSF partition).

2. The device doesn't detect rotation. I double checked the kernel option and it seem all the iio and acceleration related drivers are checked. Any suggestions to addressing this?

3. If double boot can't be done for my device and I need to install only Android, will the make iso option include the installer?

Device: Teclast X98 Plus A5C6

Thanks!