Daplink & Arch Pro board

Since I installed the latest daplink firmware on my Seeedstudio Arch Pro, I get a FAIL.TXT file with this content:

error: Flash algorithm write verify command FAILURE
type: target

…every time I drag&drop a .bin image built with an offline toolchain (which worked flawlessly with the original firmware). However, new images built with Mbed Studio or online compiler don’t show this behavior.

What am I missing?