Anyone else having problems with shifting? sometimes gets stuck in Park..other times I can not get it out of neutral and other times it is stuck in High....I have tried "rocking" it..no luck....I have also tried "standing" on rear brake pedal with not luck and also tried pressing real hard on both brakes....is there a linkage adjustment from brake(s) to shifter that I can adjust or should I just take it in?

Thanks....less than 10 hours on my 2017 CForce 500

The 500s shares the same chassis as the 400. Some have had the problem. Check that category. There will be more info there. There is an interlock, but I don't know too much about it.

I also have a 2017 500s
Since I had the fix for allowing the engine to start in any gear installed I haven't had a problem.  When I stop and kill the engine I make sure the transmission is in the gear for the direction I want to go. The transmission will hold you from moving (unless it is really steep).  Step on rear brake, start engine and go.

Got a 400, shifting get better with use, got 500 km on mine and shifts better

This is a very simple fix. There is an interlock between the foot brake and the shifting mechanism, when pressing the foot pedal the brass pin retracts from the cams on the shift lever. You need to take apart the cowling to gain access to the interlock pin at the shift lever. Behind the pin you will see a lock nut which needs to be loosened, you may then adjust the pin set screw to the point where it functions properly or back it out far enough so that it does not function at all (my choice).
Good luck.

Adjust or remove the cable that goes from the breake pedal to the gear shifter. You maybe need to adjust the gear selecor rod that goes on the left side of thr machine. On my 500s i have removed the cable from the foot pedal and adjusted tha selector rod and it makes a difference. It will shift a bit smother when you have used it for a while