Thank you for your question. Please also include a screenshot of Pega Robotics Studio. This would help diagnose the issue with "List Windows".
From what I can see in the "error.png" file attached, it seems like you are interrogating the toolbar instead of the individuals buttons. Make sure the black outline is around the element you are trying to create a control for before releasing the mouse button. I have included a screenshots for reference.
Actually I have the same list items as yours on the "list windows example.png image", and I can highlight the toolbar only. I attached another screenshot where you can see the hierarchy tree. Toolbar was added successfully but the buttons are not showing and I already tried several times to release the mouse button on different places but is still the same.
By the way, I did not have any issue to interrogate the login window, listed as "CRMfrmLogin" on the hierarchy tree.
I went ahead and tested interrogating the CRM app on the version of Pega studio that you have installed (8.0.2014.0) on a windows 10 machine. I was able to interrogate the buttons on the application.
I recommend reinstalling the version of Pega Studio you have or if possible updating the latest version. Please let me know if this does not resolve your issue or if you have already tried this solution.
Actually I'm using Windows 7 Professional Service Pack 1 because I had to migrate to this version due to incompatibility with Windows 10. I already reinstalled Pega and unfortunately the issue persist.