Hello,
1) You can use custom footer. Use Static Blocks option to create custom footer layout http://xstore.helpscoutdocs.com/article/47-static-blocks and then choose this static block in Page layout options during page editing.
2) You need to make changes in template files. Copy
xstore/woocommerce/content-product.php and xstore/woocommerce/content-product-slider.php files into child theme and move the categories code below the title, for example http://prntscr.com/gmngo7
3) Don’t understand what exactly you want to change. Could you explain what you want to change and I’ll sen you the correct code?
4) xstore/woocommerce/single-product-content.php
Regards