John E, Your friend collin above has discribed litho very well, I use 1/64th plywood as a backing when building superstructure, and use contact adhesive to fix the litho to the wood. There is very little movement in the two types of matierials, I find more movement in plastic, as for hull plating you will not find a better matierial, you can shape it to most shapes it will bend in two directions with a little gental persuasion.
Cutting, on small pieces I use a pair of sharp sissors on bigger pieces I use a straight edge and a sharp Stanley Knife, use very light strokes , dont try to cut though in one go, 3-4 light strokes, this saves your blades and your fingers.
Making things round, bend it over a piece of round plastic or copper pipe.
Deck plating, turn the litho over and lightly score on the back the size and shape you need, I use a small dulled down old screwdriver for this job.
If you want to make small objects like ammo lockers, I cut them out of a small piece of timber, just under size, if I need 6 , I cut them all and stick them to the back side of the litho with super glue, leave to set, then with a pair of sissors I trim round the timber, when done , glue all six on the next side, carry on till all the sides are covered, I normally sand each edge before glueing on the next piece of litho, only takes a few seconds, to finish you put on small feet and small hinges.
I hope this helps you to understand Litho plate.