Thank you for a good product!

I would like to draw a VOI on PET scans, using the 'Automated VOI' tool in MRICroGL before manual editing.  The 3D tool works, but does not allow me to set the constraints required, or 'append' to an existing VOI.  I have previously used MRICro to do this with success.  My operating system is Windows 10.  

I would appreciate any suggestions or clarifications.

Best regards
Stephan Malherbe