Hi,
I use nRFgo Studio(v.1.21.2.10 win7 x64) "Program Application" to program the combined file(SD+Bootloader+application), it will indicate an error as the attachment. The problem could be seen on all 52840 chip. However, it's ok if I use command line to program it.
But for some 52840 chips, when I use nrfjprog to program, it couldn't program and stop at "Initialzing the QSPI peripheral". I have erase all before programing. These chips couldn't use nRFgo to program, too.