Hi D-Money , we've missed your topic in a period while a lot of beta testing discussions were posted by beta testers (an invisible tag for normal users, but visible for us in the discussion overview list). Unfortunately we've apparently missed some regular support discussions. Sorry about that 🙁
About this issue, this isn't a Buttonizer issue and unfortunately we can't do much with it. This is a browser 'thing' and is due to the fact that the viewport (height of the page) changes in these situations. This happens with other floating content too.
We haven't found a solution yet and it only appears to happen with browsers that hide the address bar while scrolling. If you have somehow found a solution in the meantime we'd like to hear it 🙂