We fixed the shop page issue. On your website, there was two shop page. One shop page is empty and the other one is real shop page.
So we removed empty one and add the correct shop page menu.
And for the footer & subcategory problem:
For some reason, footer widget contents were changed on appearance->widgets.
So we reset that.
And to show the sub categories, you need to set the "depth" value on product category widget setting.
Original depth value was 1. So we set by 2.
If you have any other questions, please let us know again.
Best Regards, C-Themes