ZAVior, the "winter" button won't stay depressed when you push it. It should, however, light up a "winter mode" light on the dash but that light could be out. Like PK said, the winter mode starts the VX off in third gear to avoid wheel slippage on slick roads. After about 10-15 mph the winter mode turns itself off and the VX should act normally until you come to a stop at which point it turns itself on again to start you out in third gear. Maybe try pressing the button again (just once) at your next stop and see if it helps any.
I'm hoping that that is the easy fix, but if you had your fluid checked, and topped off correctly (there is quite an involved process for filling a VX transmission) and the issue still persists, then it may be something else. As others have said, the mode selector switch may be going out, but when that has happened to others here, the gear selector lights usually go a little hay wire, flashing back and forth. The mode switch is fairly easy to get to, take apart, clean and put back in so that might be the next "easy fix" to try.
Good luck and welcome. Always good to see another CO VXer in the mix.
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