Steve,
The engine light could be any number of things, but generally isn't anything catastrophic. The first thing to check, and I know this sounds silly but it works, is the gas cap. When you tighten it down make sure that it clicks at least three times to make sure it's sealed good and tight. Sometimes that's all you need to make the CEL (check engine light) go off. Also, when you bought the VX did you bring it up in altitude? Sometimes when I drive around the mountains my CEL will come on, but it's usually just due to a drastic change in altitude and it usually goes away. If that doesn't work you can go to your local Autozone/Checkers/O'Reily's and have them read the engine code (usually for free) and then bring that code back here and a few on the site may be able to tell you what the code means.
When does the transmission downshift happen? Right as you let your foot off the gas, or as you're coasting to a stop? My VX has had a hard downshift (probably to first) as I come to a stop since the day I bought it. If you only get a hard downshift then it wouldn't be the mode selection switch which has gone out on a few fellow VXers and causes some harsh shifting in both directions.
As for the windshield washers; another stupid question-there is fluid in the reservoir right? If you put some in and it seems to quickly flow back out then the hose leading to the washers themselves may have fallen off of the bottom of the reservoir (mine does this at least once a year) and you'll just need to put it back on. If fluid stays in the reservoir then check to make sure that the tubes leading to the washers aren't kinked or pinched anywhere. If THAT'S good then check to see if the washers, themselves are clogged with gunk (wax, dirt, etc.) If that's all honky-dory when you pull the stalk to use the washer can you hear the pump in the reservoir working? If not it may be disconnected or just kaput.
Hope some of that helps. Make sure to get into the search function to hunt some of this stuff down.
None of these sound that serious so I wouldn't second guess you're purchase. The VX has it quirks, but that's why we love them.
Welcome to the family.
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