What I want to achieve is "Show Pictures" as default action from the group, launched when I click LMB on the button. Neither selecting "Begin a Group" for "Show Pictures" nor dragging "Show Pictures" to the top gives me the desired result. "Slideshow" is still default action.
Directory Opus 13.10.2 (Beta) Build 9021 x64
OS 6.1 (B:7601 P:2 T:1) SP 1.0 "Service Pack 1"
I think what you want to do is create a "Menu Button". You have to go to "Insert new" (visible in the screenshot) > "New Menu Button".
A menu button basically is a button that also has more expandable options like a menu.
Edit: You can also try right clicking the "Slideshow" button on the toolbar and hitting "convert to menu button" (it might already be one though), then copying the command actions and stuff from the Show Picture button and putting it in the slideshow menu button.
Copying "Show Pictures" button and then
Paste > Replace main button
does trick.
Thanks for hints.
Ah cool I didn't even know that was an option, good to know