I disable the zoom on a diagram by setting the zoom property to 0 and it works.
Unfortunately it crashes the pdf export with the following error:
This is a dojo where the issue reproduces: https://dojo.telerik.com/EveCAnAq
I did a quick investigation in the library and the culprit seems to be the first line of the below function. _zoom is either zero or undefined resulting in NAN.
When exporting a diagram as a PDF, hidden shapes still visible.
Reproduction of the problem
1. Run this dojo - https://dojo.telerik.com/oRUPUHOb/4
2. Click on "Mask" button
3. Click on "Save as PDF"
4. Open the exported PDF file
The shape State 1 must not be present on the exported PDF