Bulk edit Easy Chart Tag dataset

I am trying to add a large number of tags to an Easy Chart instance, there seems to be no way to edit the dataset outside of Dataset editor.
I am currently trying to use an export to CSV of the dataset, then importing it again using scripting, but the changes don’t persist.

Is there something I am missing here? The script uses the system.dataset.toCSV and system.dataset.fromCSV functions without any errors.

They won’t persist if you also have a binding on the property. Disable any such binding if you are going to populate the dataset via scripting.