LS 2.00+:
Navigation Buttons - the "back" button and the "next" button, do not show at end of the page of a group the questions in half of the poll, in all the logic has not questions blocked that group or the next group.
any solution? .. thanks.

Which template are you using? Please provide screenshots or access to a sample survey.

And maybe you have some HTML error in a question, for example a <script without </script>

Denis

Another explanation: You copied text for your question/answer/welcome text/etc. from Word which includes alot of invalid crap HTML.