Just having a quick look at the TYPO3 website and it doesn't look much different from many other CMS's. The system requirements are Apache, PHP4 and MySQL, which should all work on PAYH. PAYH now has PHP5 on, but I think in large it is backward compatible. I've only found a few bits that work differently.
Superusers are not staff, but they do have a direct line of communication into the business in order to raise issues, concerns and feedback from the community.