Uploaded live site – broken images, and various broken WP features

I just uploaded my company site in this temporary url for testing purposes:
http://shopkleancolor.com/

I have done this upload on another domain as well, and while it went fine on that other domain (which I recently took down), this new upload wasn’t as smooth.

1. A number, not all, of product images show up as broken.
2. I tried to fix this images manually by going through each product and reselect the images from the image library – however the product gallery upload feature is broken as seen in this screenshot: https://snag.gy/taPGRu.jpg
3. A similar error can be found in the Add New plugins page in that it’s stuck on a loading screen: https://snag.gy/gbIusO.jpg. Plugin installation can only be done using the Upload plugin feature.
4. Updating any pages in the dashboard now leads to a blank white page. The update itself still counts, but I have to hit the back button to get out of the white page, as opposed to what should normally be an automatic redirect.

I did a lot of troubleshooting already but to no effect:
1. Reinstalled WordPress from the updates menu.
2. Disable plugins except Woocommerce to find the culprit, but no effect.
3. Reinstalled a freshly downloaded Woocommerce plugin.
4. Repaired and optimized the database via phpmyadmin.

I have no idea what to do now.