Note: This does not work with most proxies on the theme store. So far, this is for apps only. I am not responsible for any trouble you may get in. This is a guide, so please be careful to not get caught.
1. Go to the Chrome Theme Store on your Chromebook
2. Download an extension known as "Chrome Extension Source Viewer".
3. Proceed to download an app called "Chrome Apps & Extensions Developer Tool".
4. Find an app that is blocked. I will be using FHS+
5. Click on the app, not the add to Chrome. Then click on the "CRX" extension you just downloaded and click "download as zip".
6. You have now downloaded it, click the notification that appears at the bottom of the screen, then the folder will be opened.
7. Proceed by selecting all of the items from downloading the item, then copy it, and then paste it into a new folder.
8. There is a file in the folder called "_metadata". Delete the underscore, and open Chrome Apps & Extensions Developer Tool.
9. Press "Load Unpacked" and select the folder.
10. If it works, enjoy!