Gonzo,
Keep the fermentors in the house and find a closet or cupboard. The swing in temperature won't be complimentary to your mead or beer.
Sounds like the fruit was added to the primary in your third batch. I doubt that your SG reading is accurate because of all the chunks floating around. Just measuring the liquid is not accurate in this case, at least that has been my experience. Between the pineapple and the oranges your pH may trend toward the acidic side which could slow fermentation, stress the yeast, and produce off flavors/odors.
You need to post your exact recipe for us to help.
Also, you really need to get a good book for reference's sake (Ken's Book is great for this) and read it. He covers a ton of stuff including many of the questions you're asking here. Spend some time looking at the other posts here, along with using the search tool and a lot of your questions will be answered as well.
We're here to help out where we can as a supplement to your growing experience and knowledge of mead making. Mead making is a learning processes, and as with most other learning processes it is incumbent upon the student to do the learning in the lecture, lab and books. This forum is the lecture, the lab is your meadmaking space in your home. Now it's time to hit the books.
Keep asking questions, we'll be here.
Cheers,
Oskaar