Thank you for your feedback
Root cause: nVidia GTX 9 & 10 series display card has the "ROV" feature, but there is a ROV defect in recent updated driver witch will cause iClone to crash.
We can only bypass this error for now, but there are still a few cases that cannot be solved.
If you are using GTX 9/10 series display card and having the following issues in iClone 7.21:
* Freezing issue while rendering video.
* Crash caused by Billboards contents.
Please do the following steps for the workaround:
1. Download this zip file:
https://drive.google.com/open?id=1SmpkoGXXHpEpRbUY9_wjthkYIA6PRDJk
2. Unzip, and run the IC-7-Rov-OFF.reg to turn off the ROV feature in iClone.
3. Restart iClone.
We will update iClone to avoid the crash caused by ROV issue in next patch.
Reallusion I can confirm this on my system.