Hi Shuko,
Yes, you may try v16.4.0.46 for free. Please find the below link to download the trial version of NuGet with version ”16.4.0.46”.
https://www.nuget.org/packages/Syncfusion.Presentation.Net.Core/16.4.0.46
We have checked this with version - “16.4.0.42”.But, we are unable to reproduce the reported scenario from our end, while performing group shape cloning with both dummy data and also data provided from your side.
Please find the sample with dummy data which is created from our end to reproduce the issue using code snippet provided from your side.
If still you face the issue, please provide us your culture settings details. This will help us to proceed further in this.
Thanks
Meikandan