Problem solved... and it wasn't that, thanks for mentioning it
though.
The clue was in SOME import rules still working, just not the three
most important ones. I had it searching for
"From owner-blah-blah"
in those three groups (yes, that string minus the blah-blah &
quotes) and it worked perfectly using UQWK then IMPORT to get them
in. But, changing to VSOUP (ditching UQWK/shell) also apparently
changes the header, thus my search string bombed out. Shortening the
search to more relevant characters solved the problem. It must be
some difference in the header, because I simply can't believe that
three separate lists (this one included) would change the headers at
the same time and nobody else notice it, too improbable. It has to
be a difference between my ISP/UQWK vs ISP/VSOUP access.
Moral of the story:
Keep your filter search strings short and totally unique to that
list/etc you are filtering.
Thanks to all who who helped out.