I love making WAGS( Wild As* Guesses :-) ). The first thing I would try is try using a different form of subroutine call. Like:

-command=> [sub_routine_name],
#or
-command=> sub {  \&sub_routine_name  }
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I have a feeling the way you are calling the -command, it is processed as the button is created, something you don't want. Like I said....a WAG. ;-)