Just came back from the marina, everything went well. No problem with the downgrade at all. Even the reset worked by it's self. And my charts are working again. The only thing I have to test is the sonar, but I think it will work too. Just to make sure, and be prepared for all eventualits, yes I would like the v 3.40 too.
Again Neil and Catymag, thank you very much for your help and assistance. Hopefully I can help somebody, someday too.
With best regards from Polar Cirkle
alex