Hi,
The vendors shouldn't have an access to the backend.
HikaMarket does not handle vendors in the backend, it handles vendors in the front-end ; providing specific features for them.
So no, HikaMarket won't override the HikaShop backend because it is not his goal.
Like I said in my previous message, the edit of shipping/payment will be made in a future version.
I don't know how I could implement it in the backend without having it in the front-end (and it will be more complicated to do it now in the backend than the implementation in the front).
I am sorry, there is nothing for the moment for the vendors. Only the website administrators can edit the shipping/payment methods and set a vendor for them.
We are working as fast as we can to finish the implementation and providing the most flexible (and easiest) way to let the vendors configure it.
Kind 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.