I have been using SolidWorks with the Upchain plugin installed. Our team shares seats and rotates access to the licenses. When using SolidWorks without an Upchain seat, the notification pop-up indicating that you lack a seat can sometimes appear behind the main SolidWorks window. When this happens, and you perform another action in SolidWorks, the program may freeze. In such cases, you need to locate the dialog box, but the 'OK' button is unresponsive. It's a complete lockup.
I am fine with the pop-up appearing to let me know that I don't currently have a seat; however, it causes what I am working on to be locked up and requires me to force close SolidWorks, losing any work I had done over the 10 to 20 minutes.