I put in a shortcut and nothing happens, neither in the tryout pane nor in the apps.
Hi, and welcome to the forum! 
Sorry to hear about this issue.
Can you try reloading the extension and see if that fixes it? Just right-click on any webpage and select "Reload" under the Text Blaze menu item.
If that doesn't work, can you shoot us an email at support@blaze.today and we can set up a time for a quick video call to look at the issue together.