Hello,
The edition of manufacturer by the vendors is quite complicated.
While the categories are organized in a tree ; it is possible to have a category associated to a vendor and allow him to edit that category and the sub categories.
For the manufacturers, you have a list which is shared between the entire store.
It is difficult to allow a vendor to edit some manufacturers and not other ; while in the same time he can choose any manufacturer while editing a product (so he could choose a manufacturer created by another vendor who could edit it and change the name...)
Unfortunately, the manufacturers should be only be handle by the store admin and your vendors should ask for manufacturer creation.
So you can avoid duplication and modifications.
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.