That's yet another bug in Prime which still is not fixed in the current version (9).
When I open the file in the German version of Prime, the error message is "Unknown error...".
When I open the very same sheet using Prime with the parameter "/culture:en-US", the error message is "These units are not compatible" (of course again at the wrong position without any clue as to which units are meant and without an option to trace back to the correct position)..
