I'm not sure that I understand questions #1 and #2 (maybe because of my unfamiliarity with your application), but in #3, it sounds like you are just trying to rectify "24" as being your zero value. If all other values are correct, then I would suggest simply using a case structure that passes all values through except for "24", in which case it would return a zero value.
If you still have unanswered questions, I would recommend starting a new post with them. Three pages is pretty deep for a single post, and starting a new one will encourage more people to glance over it and offer their help. Also, the more you can break down the problem, the better. People are often deterred by the posting of entire projects.
E. Sulzer Applications Engineer National Instruments