I would like to have some sort of (visual) tool that can show what data is stored in dataset A and convert bits of it to Dataset B.

I do not want the entire dataset just bits of it i.e we could spend hours creating a series of doors, gates etc., we may inherit a dataset from someone else, thus to be able to view its contents and select the bits you want to copy to another dataset would be of great importance.

OK we could copy paste from the xml files and cell files etc, but this is a risk that needs to be avoided.