Hi anonomous_programmer,
Flashloader code is used to let the customer download the code through the USB HID and the UART when in the serial download mode. In fact, when you download the code, it also will load the flashloader to the internal RAM at first. That's why you find the flashloader is the RAM project, not the Flash project.
If you want to use the SPI to receive the command to program the chip, I think you may need to design you own flashoader, as the SDK flashloader just support the UART and the USB HID, more details, you can check the SDK document:
SDK_2.8.0_MIMXRT1024-EVK_doc\docs\mcu-boot\MCU Flashloader Reference Manual.pdf
SDK can be downloaded from this link:
https://mcuxpresso.nxp.com/en/dashboard?uvid=312465&to_vault=true
About the flash reside flashloader, you can refer to the RT1060 otabootloader:
SDK_2.8.6_EVK-MIMXRT1060_freertos\boards\evkmimxrt1060\bootloader_examples\ota_bootloader
Wish it helps you!
If you still have questions about it, please kindly let me know.
Best Regards,
Kerry