I have a slider going on homepage in the slider widget (not the wide one). I built a rather long pulldown menu. Then, when I mouse down that pulldown acroos the various menu choices, the menu disappears exactly when my mouse crosses over the pagination for the slider’s images. This bug was so bad, that I could not possibly select one of the lower menu choices.
So, I went into the settings for the slider and turned off the pagination display. Voila! That fixed the problem with the menu. However, if I really wanted the pagination, the problem is not fixed. This is a software bug that should be fixed, but I am not personally worrying about it, since I found this workaround. Here is my webpage http://answeristhefood.com/ where you can see the long menus, but since pagination has been turned off you can’t experience the problem.
Another workaround for others is to break up the long pulldown menus into short subsets, like have subs called A-L and M-Z. If you are not sure how to do this, in the menu edit section, click on links on the left and type # in place of the http:// and then type A-L (or whatever you want it to say) in the field below that. Then, Add to menu.