Just to cover the basics as mentioned in the BSP guide the CapsuleApp.efi and the *.cap file are a matched pair and must be used together. When a new *.cap file is released, you must use the corresponding CapsuleApp.efi to install it.
Also I have found a couple of post related to issues with the UEFI , the behavior of your Galileo is different but I think some recommendations are applicable to this situation:
Re: Unable to open serial console session (cable, host OS issues, double check the UEFI shell)
Re: Restore Galileo grub file (I would check the SD card format and size or corrupted partitions)
Sorry for the late response. Actually I do want to enter UEFI INTERNEL SHELL and use the same version of *.cap file and .efi.
I tried to use Arduino IDE to burn the SPI with the original image, and finally I can access to UEFI INTERNEL SHELL...So I guess may the 782 version does not support UEFI SHELL.
Thank you for you solutions, and now I can use bsp1.0.0 now.