The mouse stops working at random everywhere within the UI. It happens most frequently in chat dialogues.
When it occurs, you are unable to select anything using the mouse. Clicking the mouse fixes the issue, but it also selects which ever dialogue choice/item was highlighted by default.
Some .ini file tweaks (iPresentInterval=0 and bMouseAccelleration=0) are suppose to improve this issue but it still remains, and is still very annoying. I am forced to use my keyboard or an xbox controller to navigate when i should be able to use my mouse with my new sixy SkyUI.
Please bethesda fix this issue. The PC gamers are the ones that keep playing your games for years after the console crowd gets bored, why must we suffer with all of these crappy console port related issues?