olaf_gy explained how to select multiple topics and move them simultaneously with the graft handle.
I don't believe that NM5 allows the insertion of overlapping topics. In other other words, it's not possible to "freeze" the layout engine to have manual positioning of topics. The system is designed to achieve maximum efficiency in the use of space for the purpose of creating mind maps. Why would a mind map creator want to clutter or confuse his/her design with overlapping topic spaces? NM5 is not a graphic design program; it's purpose is mind mapping.
I find the layout engine to be a vast improvement over NM4 from the perspective of creating mind maps that grow efficiently and elegantly. Its graphic editing tools for adding color, texture, inline graphics, etc., are better than any other mind mapping program's I've looked at. Some recent posts suggest to me that some users would like the program to behave more like, as examples, OmniGraffle or Adobe Illustrator or Quark. That's just not the sort of application that NM5 aims at. It's for making branching patterns from a central hub that flow out and around the center. That's what mind maps are.
Anyway, it is possible to make NM5 maps look more like, say, a genealogical chart, but that would be silly and a waste of time. There are programs specifically designed for making flow charts, genealogical charts, architectural layouts, circuit diagrams, organization charts, etc. etc. NM5 is for a specific intellectual and creative purpose: mind mapping. Perhaps users who expect more or different things from it should review the concept of mind mapping and look at the fine examples provided in the help files.