I don't hope so, but maybe you were a tad too fast with your order...
I've just read several Norden 901 threads and it seems to be a big difference between Euro 4, Euro 5 and especially Euro 5+.
5+ seems to be very sensitive to changes to the system; the oxygen sensor is causing the mail function codes.
I just stumbled upon the fact that the Coober solution is supposed to be fully compatible with the Euro 5+ Svartpilen and Vitpilen 801.
So maybe it would be the better solution?
HUSQVARNA 801 SERIES LM ECU. The only ECU on the market with full EUR5+ support. Pre-Configured and Plug-N-Play.
www.coober.eu