We have a 2011 Shamrock 19 too.
I pump the tires to 65PSI, put my tire covers on, raise the front jack a tad so the trailerr is not level - to allow water/melted snow to fall off.
I do not put the stabilizers down, if a tire had a flat, it would put too much stress on the jack I believe. I do apply a generous coat of white grease to protect them from rust.
Denis & Diane
2010 Sabre 31REDS
Ford F-250 2011
* Happy Campers *