system:

7600/g3@400 MHz
120MB RAM / 2.2GB HD
OS 8.1, Macintosh Runtime Java 2.2.5

problem:
when launching installer, i get the dialog /progress bar:
"Install anywhere is preparing to install... This may take a few moments.
Extracting this application's installer [ Cancel ] "
the progress bar proceeds all the way to the end,. then says, "Running this application's installer" for about 1/10 of a second, then says "Quitting", for about 1/20 of a second, and quits.
this was found out by using the Mac Snail control panel, which slows down fast systems so you can emulate a slower system. really useful for inspecting messages that flash for less than half a second.
this occurs with or without extensions enabled. in either case, the end result is that nothing is installed. it's not freezing, it's just not having any effect.

suggestions?

strictly harmless and sometimes normal,
peter