Front screw on right side of the frame retains the cylinder. Remove that screw and clean cylinder on routine basis. Unless you have a good knowlege of the inner working of the Smiths, I would not recommend further disassembly.
Keep the area under the ejector star clean and DRY. Oil in this location will attract fouling and can cause hydraulic misfires.
Dry firing is OK in most all modern revolvers, but snapcaps are better. Just REMEMBER, there is NO SUCH THING as an un-loaded gun. If you get careless when dry firing, someone may die. *** Please be careful ***
One of the tricks of the trade is to get a good trigger job done on a Smith revolver, it must be dry fired about 5000 times. That allows the friction points to be revealed so they can be smoothed. it is also like a 1000 mi break in on an engine. It will smooth out considerably just from dry firing that much.
I recommend a very specific procedure when doing dry fire (for practice or break in). Put ALL ammo in a different room. Check, double check and triple check to insure the gun is unloaded. When dry firing, still insure you have a safe back stop in case of cranio-flatulence. If the gun leaves your hand, recheck for unloaded status. If you get distracted by a phone call, recheck for unloaded status.
When done dry firing (this is the really important part), DO NOT LOAD THE GUN. Put it away and do something else, not gun related. Do the dishes, wash the car, something that will reset the muscle memory so you will not unconciously pull the trigger when you reload.