Currently the widget displays all the vendor’s categories and children by default, whereas the normal product categories widget has an option called “Only show children of the current category”. Would it be possible to duplicate this so the Vendor’s category list can be shorter?
We have checked from our end on your site and couldn’t recreate the issue about the announcement section. Can you please send a screencast video or elaborate the query further? Is the functionality not working as expected or do you want to modify the CSS?