I just completed the White Skull Canyon module and, on the screen after a battle, a text box is displayed across the bottom of the screen and does not allow me to click on the 'Collect Loot' button. Changing the display to fullscreen does allow me to click on the 'Collect Loot' button again since the text box is now further up the screen.
You must accidentally have opened the console - this happens when pressing F1. Press F1 again and it's maximized, and once more to close it. Hope that helps
That must be it. I just signed out and logged in again to get rid of it. Is there any documentation regarding keyboard shortcuts, UI stuff, or the full rules of the game? I can't seem to find it in-game at the moment.
That's not an official shortcut - mostly there to track bugs et c for the beta I believe. They just added game rules to the menu, just press help after escaping and you'll get a nice link.