One of the features that makes UberMenu so flexible is the ability to place widgets and shortcodes inside the menu to generate advanced content. If you are adding a shortcode or widget that has advanced styling, or which has a javascript element, you’ll likely need to tweak a few UberMenu settings to ensure they function properly.
Styling
Since you’re placing custom content inside the menu, some of the menu styles may apply to your widgets or shortcodes, altering their display. And note that because your widgets/shortcodes are not being placed in a theme sidebar or content area, their styles may not apply when they are in the menu (this depends entirely on how the widget/shortcode was coded.
To minimize the effect that UberMenu has on the shortcode/widget styles, you’ll want to disable Reset div and span styling in your UberMenu Control Panel > Theme Integration
Scripting
Some themes which aren’t coded modularly have javascript that will interfere with UberMenu even after the theme menu is replaced. To combat this, UberMenu has a setting called Remove Theme Conflicts which will attempt to block those scripts. A side effect is that custom javascript that IS supposed to act on the menu may not function. If you know you have javascript that should run in the menu, or you are writing your own javascript to affect the menu, be sure to disable this setting in the UberMenu Control Panel > Theme Integration.
A possible result is that you may reintroduce residual scripting from the theme which may need to be addressed so that the menu can function normally.