FWIW, Ray Cologan did a demo of a floating navigation palette that made buttons available in preview mode as far back as .fp5. The demo file can be found here
http://www.nightwing.../demos1.html#d2
Don't know if it can be adapted to the more recent versions but I seem to recall that the technique was fairly simple but incredibly clever, as is the case with most of Ray's work
Hth
Phil
I just converted this solution to FP7 to see if it worked and it did... and it made me smile it is so elegant. I have attached the file in case it helps.