Strange results in deletion of lines

[David C.]

Just want to offer a BIG thank you to everyone who has replied.

By trying different variations of the coding strategies offered, I was
able to make the program run flawlessly *AND* adding several optional
processing options (like the "F" numbers and similar), all while
cutting the overall run time down by approximately 65% in the process!

As for simplicity in the final product, the user will select any of
three check boxes, push a "run" button and save the results when it's
finished. I cannot imagine it to being any simpler for them.  :-)

You folks are just awesome!

David C.