I’ve been having the same trouble. Could be we have been selecting the wrong target. I’ve been trying to compile the code from the /samples/RCM5400W folder.
I selected code from the /samples/BLxS2xx folder, and selected BL5S220 in the project option, targetless tab.
Somewhere along the way I also hit ctrl-y to recompile the bios which might not have had any affect. Didn’t seem to hurt.
There are at least 2 issues with trying to replace the module on a BL4Sxxx board.
The first is that the board ID reported by the RCM5400W that came with SBC is different to the stock RCM5400W so that DC can autodetect the target. This is why you are seeing the error.
The second is that the User Block for the module will contain calibration information for the analog I/O which will not be in a stock RCM5400W (indeed you cannot even swap modules between SBCs for this reason).
I don’t know if Digi have a option for supplying replacement modules for the SBCs or if it is a return and rapair possibility.