I renamed my modules from Module1, Module2, etc., to more meaningful,
recognizable modules. Problem is, when I press the toolbar button assigned
to a macro, I get an error message that it can't find the macro. I need to
go to Customize and redefine each macro assignment to reflect the new module
names.

Why can't Excel do this automatically, much as it does when you move a cell
and it updates all formulas to the new location?