jba,
If this is a simple change, and IF you have the source code, I may consider doing it for you at no charge.
Email me with a description of the change, and we can talk about it. If you don't have the source code, there is nothing anyone can do, you will have to find the company or individual that created it so see if they have the source.
In general, there is nothing you can do to edit an executable (unless you know machine code, and how to correct the checksum) without the source code. Even then, you will have to have LabVIEW. It would also be good to know what version of LabVIEW it was done in, as some versions are harder to convert than others.
Good luck