To export the data from RB Logbook, you will have to export three files: one for Flights, one for Aircraft and another one for People. If you are using iOS, or want us to do it for you, we can definitely do that! If you are using a Mac, you can import this data yourself using our Importing spreadsheet files article.
You should be able to export your flight, aircraft and crew data from RB Logbook in a CSV (Comma Separated Values file) which can be imported into LogTen.