Прислали ответ из тех поддержки:
Issue is able to reproduce it. For further investigation, a change request is created with engineering team and details are given below.
The Change Request for this is: ID:INVGEN - 54029 - "Unable to hide dxf document using Open () API"
Here is our standard reply asking for a business case:
We have logged Change Request number INVGEN - 54029 with our development team as this issue requires a modification to our software. Please make a note of this number for future reference. You are welcome to request an update on the status of this issue, or to provide us with additional information, at any time by submitting a new Case through DevHelp Online quoting the Change Request number or this Case number.
Говорят что когда нибудь исправят