I've tried using the noted approach. Unfortunately; it only seems to apply the theme to the first dialog that is defined in a LUA script. Subsequent ones seem only to obey any explicitly global attributes, like those for DLGBGCOLOR. Attributes, such as control padding within the "myTheme" appear to be ignored. I've checked to see that the user theme is still specified as the default theme prior to building additional dialogs to the initial one and found that it is.

However; If I set myTheme prior to specifying each dialog, then things work as expected.

I'm starting to wonder if the LUA compilation of IUP might have a bug, but I'm certainly open to suggestions as to how to correctly utilize the THEME capability. Any assistance or examples for getting this to work reliably for multiple dialog LUA scripts would be very much appreciated.