Dear JColvin,
thank you very much for the answer. The bus reported device description is indeed "Digilent USB Device" on both serial converters. The Adept system was unable to detect anything unfortunately. The board does boot up correctly (the demo design is loaded and the leds are flashing and so on), if the jumper is set to QSPI. Everything seems ok, but it somehow doesn't want to detect the board. Could be a driver conflict or the FTDI not being programmed correctly.
Best regards,
Martin