progress on understanding .spv files

[Ben Pfaff]

I want to say "thank you" to all of the helpful people who sent me
sample .spv and corresponding .pdf files last week.  I have spent
numerous hours looking through them and comparing them against the
rendered versions.  I have not yet entirely figured out the format, but
I've made a lot of progress.  After I do some more work, I guess that I
will have some new and more specific requests for sample files, but I
don't have any yet.

Thanks again!