Creating online questionneaire (frontend, backend, export)

Server backend given (apache, mysql, php 5.2+). The solution has to meet: - Admin (backend) for add, delete, modify, import (xls, csv) questions and answers in different languages - User and group management for selecting which questionnaire has to be filled, anonymous fill also needed for each question-set - Different dimensions - e.g.: a company has to fill a survey and the management will have 100 questions, but the worker only 50 and the questions can be the same for them but in other sequence (and there can be some which is not affected). In addition the worker level could have other dimensions (maybe with the same questions, but the export should represent which area was gave the answer.) But this is just an example. - Answers could be obligatory - Logs and actual stats - Different links for the surveys with user and pass access (however anonymous survey fill will be needed it also has to be protected with user/pass - avoiding someone accidentally finds the page) - Template creation and backup/keep the earlier created questionnaire and the answers for it - Export to xls - Frontend has to be configurable (intro text with logo and pictures on the first page), background, font type and size and layout has to be chosen by the admin. Also could be accepted a currently working version if meets the needs.