There is a Read-Me file for download at the Curious Labs site (the page with Poser 5 downloads) which lists all the corrections in the Service Release. I would hesitate to run Poser 5 on a Win 98 machine... The bad memory handling in Win 98 appears to give Poser 5 users problems. You should consider an upgrade to a NT based system (NT/2000/XP) to take full advantage of Poser 5.