Well... you don't HAVE to follow that advice. For coding changes, be sure to use the over rides, but if you are simply adding a couple fields that are very specific to the products data, put them in the PRODUCTS database. Things will be MUCH simpler, you'll have fewer SQL requests, and actually LESS core modifications.
Next version? Weeks... Months? Depends on my work load and if I can get some free time. Next version will be submitted to the zencart downloads, so I want to be sure it's solid and well documented.
-chadd
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