Hi Jonathan,
Thanks for showing keen interest in Aspose.Slides.
The shapes don’t have unique Id in PPTX format, so it is a limitation of PPTX format. Once this feature becomes available in PPTX format, we will try to support this in our product as well.
We are sorry for the inconvenience.
Mudassir Fayyaz
Support Developer
Aspose Sialkot Team
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