Hi Tom
I use SQLite Maestro, you can get a free months trial from there site if you are interested, then I think I paid about £65 for a full copy.
It took me a while to work out how to do certain things, but there is a lot more to the program, that I do not know about.
I am lucky, that I saved a copy of NavData.db3 database at the start when I first installed RB, so now I can run RB and work on the original file, then when I have finished updating it, I can just replace the one I am using now.
Cheers
Andy