Maxplus II download required 9.01

I need 9.0 in particular because we have a safety-critical, certified design dating from 1998 which requires a modification. To change toolset revision (9.0 was used for the original design) will involve a huge amount of work in satisfying the certification authority that the tool change has not introduced the possibility of a systematic error in the rebuild. We've now downloaded 9.0 from the FTP site but have run up against the next hurdle of requiring an authorisation code for the licence.