Hi, even an hour before it starts raining, I see slugs nearning the entrance of my hives. They feed on dead bees. They know in advance that there will be dead bees dropped out by the cleaning bees. I have never seen slugs inside my hives (most are styrofoam). About mice: I leave on purpose a small empty styrofoam box (Apidea, mating nuc) on the ground, free for any mice that would seek shelter. I give them a dry and warm place to build a nest and they do not bother the hives, that my experience. I have checked in winter and there is usually 2 to 4 mice living in there. They build the nest with leaves and other materials. My entrances are 3D printed with PLA, in winter I keep a very small entrance, height is like only 7 mm. No mice ever got in. About condensation water: I tilt my hives forward 1.5 to 2.5 degrees to help water to evacuate, and help the removal of dead bees. Good luck and cheers.