What versions of PSP are available, and which run on which OS?
PSP Version 3.0 through 3.12 and PSP 4.10, 4.12,and 4.14 are widely used. The final version of PSP 5.0 is now available, too. Only 3.12, 4.14, and 5.01 are available from the Jasc website last time I checked. Upgrade patches are available for registered users of 3.1 and 3.11 to upgrade to 3.12, and for registered users of 4.10 and 4.12 to upgrade to 4.14 (3.1 to 3.12 and 4.10 to 4.14 requires two patches, applied in order.) PSP 3.x runs on Windows 3.x. and NT 3.51. (And under Win95/NT 4?) PSP 4.x runs only under Windows95 and NT 4.0 or better. PSP 5.0 runs under Windows95/98, and NT 4.0/5.0, but has features (ICM 2.0, whatever that is) which only work under Windows98 or NT 5.0. I don’t know if 3.x will run under Windows 3.1 over OS/2. I also don’t know if PSP 3 or 4 will run under Wine on Linux (I haven’t been able to get PSP 5 to work this way).