Calendar error

Hi.
I'm having a issue. When I click on a specific date and event in the calendar (or more like hovering over it) the content disappears. For e.g. If a have a event on the 9 of aug, the event name will display in the calendar month view. But when hovering the mouse over it the content inside the date square disappears and I have to refresh the page to get it back. Is this a bug or something else weird or just a setting that I missed?

Anyone who knows how to display a set of categories lpfor e.g. above the list view (banner). Maybe like it is on the demo page. I saw somebody posted the same question and got a reply but I can't find where to do it.
Or maybe better, to filter the list view. Like if I have 20 events in the list, and them can click a category to reduce the list content so only the chosen categories are shown, but stilll in the same list view like a easy tag filter system that many modules have.

Lastly anyone that can recommend the best event module for joomla. Need a good one with filter options, categories, venues etc but without having to leave the actual page, and it has to look good.

Our happiest users gave always enough informations about their sytem. If I remember right there was the.same problem with a system where additional template or plugin made interferences.

So then it must mean that it's nearly impossible to find out, the issue if it's because of a module. And if it's the template then I need to change it, which I don't prefer to do.

Do you have a solution for the category?

Sorry, but I don't understand what you want to ask. May be some printscreen
Or images help. Is there someone who understands?

I mean the category view that is on the demo site. How can I use it?

you create a new menu and choose categories. In the menu settings tab of categories you can choose different settings.