3D menu mouse input issues

Development Programming & Scripting
1

We discover that Buttons, CheckBoxes. ComboBoxes and Sliders has big problems with proper mouse input handling where showed as 3D widget.
The problems show only in standalone or build run, in editor everything working ok (except invisible ComboBox menu, of course).

  1. Button - ClickMethod EButtonClickMethod::DownAndUp does not working
    We found that Button is losing capture (from FSlateApplication::TickApplication QueryCursor() call) after LMB press without any visual reason.
  2. CheckBoxes - ClickMethod EButtonClickMethod::DownAndUp does not working
    Cause: Like button no MouseCapture in OnMouseButtonUp method
  3. Sliders - drag is not working.
    Cause: Like Button losing capture
  4. ComboBox - we must press LMB twice to change selection in combobox list, 1st mouse down highlight item, 2nd change selection
    Cause: No MouseCapture in OnMouseButtonUp method

Could you help as resolve this issues?

Thanks,
Marzena