Does the Button renaming/resize still work for you with the latest Sketch version? (Currently 47.1)
The technique fails for me when I apply it to a selected symbol layer — the container’s dimensions stay put and the text simply breaks to a second line. If I go into the symbol page and apply the command directly there it does resize successfully; but, of course, it’s no longer useful that way.
I’ve been looking everywhere for a way to get symbol-ized buttons to resize dynamically to the text it contains (everything so far doesn’t seem to work in the latest version). If this does still work for you, or if you’ve adapted a new method for the latest Sketch, I’d love to know :)