I upgraded my ActiveState perl and found that Tk no longer builds correctly so I changed to Tkx.

Quick, switch back , use PPM::Repositories, install Tk

from what doc (mainly Tk, NOT Tkx) that it should work.

Well don't do that :) http://tcl.tk/man/tcl/TkCmd/ttk_button.htm, http://docs.activestate.com/activetcl/8.5/tcl/TkCmd/ttk_button.htm

Tcl::pTk will have a -background option