Getting Desperate – SLIDERS, MENUS, EVERYTHING!!!

You should be able to create any custom menu structure that you want via Appearance -> Menus. Perhaps you need to review custom menus?

Many thanks for taking the time to reply Esmi.
To just confirm – I’ve already created the menu exactly how I want it (dropdowns, etc) using the old theme, but when I’ve replaced with new theme it won’t display most of the items I’ve created because the new theme doesn’t have some of the same default categories that the old one did (so when I go to Appearance – Menus, the ones that don’t display when I view live site are ‘greyed’ out and say they don’t exist)

the new theme doesn’t have some of the same default categories that the old one did

Post categories are completely theme-independent. As are custom menus created via Appearance -> Menus.

and say they don’t exist

Ok – I’m officially confused. How can something that doesn’t exist tell you that it doesn’t exist? I’ve created dozens of custom menus but I’ve never seen any of the menu options greyed out. Can you be a little more specific?

Hi again, Yes – when I go to Appearance – Menus, all of the work I’ve done to create menu items such as categories and pages using ‘Cleaner’ theme are showing in panel but different colour to standard ‘About us’, etc pages that show up in new theme and the old ones are totally uneditable so don’t show when I preview site using new theme???

Can you replicate this using the Twenty Eleven theme?

Hiya, Do you mean recreate this from scratch using Twenty Eleven? I’ve just switched themes to that & same issue again, when I go to: Appearance – Menus, the items that I previously made in original theme are now all pink (not grey as mentioned before – sorry) and say ‘invalid’; Also to give you a further idea, on right hand side of this page just underneath blue ‘save menu’ button & above all menu items this message appears in pink box: ‘There are some invalid menu items. Please check or delete them.’
As mentioned earlier I created the categories & pages using pre-set options such as ‘Service’, ‘Testimonials’ & ‘Portfolio’ that came with the theme I bought – ‘Cleaner WordPress 2.0’ and these automatically appear down left hand side of main dashboard when I activate this theme (when I change to another theme though these options disappear & so I can’t edit under normal posts/pages/categories,etc and they’re totally invalid on Appearance – Menus??
I really don’t want to have to recreate all this – is there a simple way, plug-in or similar theme that can assist me please?

Please, please can anyone help me with this further?
I’ve decided I want to stick with the theme I’ve used from start (as I don’t want to risk messing rest of site up!) and I simply want to get the Nivo Slider (see any of previous posts) that came with the theme working properly – it’s just worked really slowly with this message: “A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.”
I’ve contacted (i) author – no response, (ii) site I bought theme from – responded, but no solution!, (iii) Searched web & forums – no solution!
As a last ditch effort, as I’ve been making site in Firefox I downloaded ‘Firebug'(although didn’t really have a clue what to do with it!) and have now totally screwed site up – there’s no slider at all & just a white space where it should be??? – so, I urge anyone, as I’m a WP newbie, to please offer me a simple, easy to follow solution to this? (will gladly send my log-in details via email or PM if this would help?). Many thanks