This is really unpleasant experience. We apologize for the inconvenience. There is a css conflict with the default Sitefinity theme and the styles of the Forest skin. To avoid all trouble use a theme different from Sitefinity default which is aimed to provide some basic styling. Then all will be styled properly.
As you know Sitefinity widgets rely heavily on RadControls and use their implementation to serve its needs. A feature of the rad controls is to set built in skins one of which is Forest. Sitefinity community edition will remain as it is for now because it provides core functionality for free and is aimed for simple sites.
These options ( a, b) are available, but not trough the backend UI, I also expect the improvement of the navigation so I am eager as you to see it.
To ( b ) the css from the skin gets in conflict with the other css applied to the page. This is expected as css applies the last rule of the same type it has so some of the rules must be changed and changing is trough editing the Theme ( all styling is there ).
PS:When selected Horizontal the user is prompted to go trough the options and this option is expanded so it is really easy to change Click to Mouse over.
the Telerik team
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