can a button's label be used as variable OR use a variable as a button's label???
Yes. This is a common technique for localizing a file. Make your button labels with $$vars and have something that loads them based on the language preference of the user. The trickiest part is maintaining your naming convention of all of those variables.
Also, with FM14's button bar segments, you can specify a calculation for a button label, so you could have that point to a table with the button label options as well.
Lots of ways to skin the cat. Search around for some demo techniques (I think SeedCode's blog has something like this if memory serves?).
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