WPFolio – help with basic menu and sidebar concepts

I’ve started using the excellent WPFolio theme for an artist site and I have a couple of questions which I’m hoping someone who uses the theme can help with. My test site is at https://sussexcontraband.com/test/

1. Sidebar widgets – I (think I) understand the concept of using categories and posts to provide a searchable reference to the content. In my test site these posts pop up in a menu item called portfolio. But if I want to use the category or tag search widget in a sidebar sidebars only display in a page entitled, news etc. not on the post pages in my portfolio menu item – how can I get sidebars to show on all or most pages?

2. If you drill down through my portfolio menu>installations & exhibitions>eco-art>dust to dust ashes to ashes – we have a big pic of a single work. How can I add descriptive text to this picture?

3. Same place.. how do I get rid of the comments counter (I’ve turned off comments site-wide)

4. The menu system only allows me to scroll horizontally across images in that post. is there a way of adding an ‘up one level’ link? It’s ot convenient to have to go right to the top level and then come down again.

Thank you for any help.