Modify resolution Android 5.1.1

Iḿ working on a Dragon Board 410c, and I want to modify the resolution of Android 5.1.1 in order to interface it with the pico proyector LighCrafter 2010 EVM from Texas Instruments.
I followed the steps mentioned in DSI Display Porting Guide, but Iḿ having troubles with the steps, I already create the boot image with the resolution modified but when I enter in the fastboot mode of the Board to install the boot I can not leave it after, that is why I can not see anything in the display.

Can somebody help me with it?

Thanks in advance.

Hope this is not too late. You can refer to previous threads here: and