Failed to import dataflows to a target environment

Hi,

I'm trying to import a solution which includes all my dataflows (6 dataflows) into another environment, but i get following error which is not really meaningfull:

I have tried also to seperate the dataflows into seperate solutions but it didnt work too.

And i added all the connection references to the solution as well. 

Does anybody have an idea?

Best regards and Thank you!