ad 1: opening popups on hovering is not possible at the moment. Havent found a way for this yet. If I do, this feature will probably be available in the pro version I am currently working on.
ad 2: popups for marker maps can be set to be open by default on page load. Just tick the checkbox "open popup" next to the popup text box on the marker edit screen. Be aware that this doesnt not work for layer maps.
PS: as I give support for free, I 'd appreciate your review at http://wordpress.org/support/view/plugin-reviews/leaflet-maps-marker ;-)