Check for multiple instances of S3D when the program starts and disallow more than one.
When reactivating S3D from the Taskbar, multiple instances of S3D can be started, possibly resulting in a crash, or losing current work.
Joel,
Do you start them from the program icon or from the entry in the task bar?
The reason I said that it because you can inadvertently start instances when you just want to re-open the current instance.
I can understand deliberately running an instance though.