My wife has made sloe gin. I put your questions to her, and this is what she said:
1. It's not worth the effort.
2. If there is any sediment at the bottom of the container that it's in now (is it in a john?), it must be filtered into another john to remove the sediment.
3. The sloe gin can then be poured into clean bottles.
4. It should be left for about 3 months before drinking.
I asked my wife about your jelly setting stage, but she doesn't know the answer. Anyway, I suppose you've sorted it by now. Best of luck.