Kwboot into custom u-boot

pi@raspberrypi:~ $ kwboot -t -B 115200 /dev/ttyUSB0 -b u-boot-spl-2019.10-tld-1.ds414.kwb -a
Sending boot message. Please reboot the target...-
Sending boot image...
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U-Boot SPL 2019.10-tld-1 (Apr 09 2020 - 16:26:57 -0700)
High speed PHY - Version: 2.1.5 (COM-PHY-V20)
High speed PHY - Ended Successfully
DDR3 Training Sequence - Ver 5.7.4
DDR3 Training Sequence - Ended Successfully
...................................................................]
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[Type Ctrl-\ + c to quit]


U-Boot 2019.10-tld-1 (Apr 09 2020 - 16:26:57 -0700)

SoC:   MV78230-B0 at 1333 MHz
I2C:   ready
DRAM:  1 GiB (667 MHz, 32-bit, ECC not enabled)
Loading Environment from SPI Flash... SF: Detected n25q064 with page size 256 Bytes, erase size 4 KiB, total 8 MiB
*** Warning - bad CRC, using default environment

In:    serial@12000
Out:   serial@12000
Err:   serial@12000
Model: Synology DS414
Board: DS414
Net:
Warning: ethernet@70000 (eth0) using random MAC address - ca:91:b6:2d:22:41
eth0: ethernet@70000
Warning: ethernet@74000 (eth1) using random MAC address - 0e:93:f0:c0:df:b3
, eth1: ethernet@74000
starting USB...
Bus usb@50000: USB EHCI 1.00
scanning bus usb@50000 for devices... 1 USB Device(s) found
       scanning usb for storage devices... 0 Storage Device(s) found
SF: Detected n25q064 with page size 256 Bytes, erase size 4 KiB, total 8 MiB
Hit any key to stop autoboot:  0
device 0 offset 0xd0000, size 0x700000
SF: 7340032 bytes @ 0xd0000 Read: OK
Wrong Image Format for bootm command
ERROR: can't get kernel image!
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