I need to install a different opencart theme on an existing site

General information for the website: We sell jewelery
Kind of development: Customization of existing website
Description of requirements/features: We need to install a better opencart theme as the current theme is ugly and outdated. Yet we have to be very careful with the current content and inventory. The website has hundreds of items + images + product details that we do not want to loose or spend time to redo the data entry. The new theme should be responsive and very easy to use.

Current website:
http://solagoldcollection.com/

Few features that should be taken care of in the new site are the following:

1. We need a POPUP message. With the following message: " Register with Solagoldcollection website so you can receive daily offers and surprises", if you click OK you will go directly to register yourself or u can close it by x

2. We need in the admin section to add (Search by code) / products - purchase, and also we show on the back-end dashboard showing some analytic data i.e. how many products are uploaded and how many products are sold, total sales today, total sales 30 days/ between dates...

3. One responsive banner with on top 3 linked buttons (ghost buttons) to (Clearance, Deal of the Day , Shop )

4. Deleting Products can only be done from super admin account: content creator should NOT be able to delete any product from the database. Only the Admin should have this option. This needs to be set in the user permissions.

5. From the admin Login we are only able to create 1 user (content creator) we need to be able to create more content creators.

6. Change the text of Check Out to >>> Buy Now (this is the language our target audience understand)

7. When they click on buy, the terms and policy message should appear in a form of a pop up that they need to accept before they proceed with the checkout.

8. We need to integrate a free live chat account on all the pages >>> Use livechat.com free version << shopping cart should alwyas hover on the right side of the page, so it will always stay visit. Cart should also indicate how many items it contains.

10. Next to Deal of the Day and Clearance links, we wants to show how much have been sold: (5% sold) until we reach the (sold out status).

11. Delivery Charges: Under 250 there will delivery charges, over 250 AED it will be free delivery. But she wants to have the ability to change this freely on special occasions and on certain sections.

12. We need for her to add a page only text, to explain about the products and how the site works, like about us maybe so this page will be adding on the left side like normal category but only text no images text only.

13. Feedback Button: When clients click on it they can add their comments and click submit. The admin needs wants to be able to approve or disapprove the comment before it will show on the site it self.

14. Stock: stock needs to be automatically update. For example: If someone buys 5 items it will be taken from the stock, BUT if the same client cancel one item in a later stage. The admin need to be able to just remove this 1 item from the original order. ( this 1 item will be taken out of the order and by doing this it will add back to the stock.)

15. A freelancer has tried to do some of the above and made the page result in php errors (which we managed to fix through another freelancer) but in his new design which we obviously don't like he missed the links to that were on the homepage which I managed to find a copy of on the web archive: http://web.archive.org/web/20130719030632/http://www.solagoldcollection.com/
All we asked is to remove the bottom three images and have the three links on the slider banner itself, he messed it all up and deleted all the other links on the page (about us, Contact us, Free shipping, Cash on Delivery, exchange and return policy). Please fix it.
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