Hello,
Product approval is not to make the product published or not ; it's made to require a store validation.
In the toolbar you can see "products to approve" ; which will list you the product that need to be approved by the store owner (via the backend or the front-end).
If you want a product be published automatically, you have to use a "product template" thus you will have a control on the default values when a vendor is creating a new product (and if the vendor do not have ACL on a field, the value in the template is used)
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.