Floppy Disk Drives
By default, PMIO does not allow the use of floppy disk drives. This is because whenever PMIO updates its disk information, floppy drives make an annoying 'grinding' sound. You can use the check boxes in Disk Preferences to enable floppy drives if you need to use them with PMIO.
256 Colour Displays
When PMIO was first written, 256 colour display cards were still used by many people and I tried to support them, although it is actually quite a nightmare to do so properly. In 2003, I should imagine that most people who want to do graphics have progressed to at least a high-colour display card. As a result, and in order to simplify the program, PMIO now officially requires a high-colour or better display card. 256 colour mode is no longer actively supported. While still present at the moment, all 256 colour related features are likely to be removed in a future version of PMIO.
Mouse Wheel
PMIO does not and never has officially supported mouse wheel scrolling. This is because so far I have been unable to decypher the Microsoft documentation on making it work on all Windows platforms. I have had reports that the mouse wheel used to work in older versions of PMIO. This was unintentional and it was probably caused by my use of a third-party component in the thumbnail panel. Since this panel has been re-written from scratch, the component is no longer used and consequently the mouse wheel has stopped working. Although not a priority to me personally, I will make an effort to officially support the mouse wheel at a later date.