Yes, Zencart is actually a spin-off of OsCommerce, but where as Os has suffered with upgrades, etc., the ZenCart dev team continually is upgrading their product, and have just released a new version that has implemented many security features, and they have also gone to a tableless design...

What version are you running? As many of the features you ask are in there already...check their site also for their dev plans, as many of the others are on the table..

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