Fairlight exports empty Dolby Atmos ADM BWF files

Hi everyone:
I'm creating a Dolby Atmos mix in Fairlight. Mostly I use the "Dolby Atmos Send" in "Patch I/O" page to route my tracks to correct channels of the internal Dolby Atmos Renderer. In this workflow I can use Menu-Fairlight-Immersive Audio-Export Master File to export an ADM BWF master correctly.
However by reading tutorials I think I can try this:
1. Creates a bus with format "Dolby Atmos Master";
2. Assign buses and tracks to the out of this bus to route everything. In my comprehension to the tutorial, buses assigned to this bus will be considered as beds and tracks assigned will be considered as objects.
Based on my understanding, I think this is another type of workflow. Everything looks correct except when exporting the ADM BWF - The exported file is blank. It does recorded the info of the mix but just without any sound.
So now I'm wondering that is this way a correct workflow? If it is, what is my mistake? I can see that in the export window, the source is called "(My bus name) assign" instead of "Dolby Atmos Send Patching", and is greyed out so I can't change it. Thanks!
I'm creating a Dolby Atmos mix in Fairlight. Mostly I use the "Dolby Atmos Send" in "Patch I/O" page to route my tracks to correct channels of the internal Dolby Atmos Renderer. In this workflow I can use Menu-Fairlight-Immersive Audio-Export Master File to export an ADM BWF master correctly.
However by reading tutorials I think I can try this:
1. Creates a bus with format "Dolby Atmos Master";
2. Assign buses and tracks to the out of this bus to route everything. In my comprehension to the tutorial, buses assigned to this bus will be considered as beds and tracks assigned will be considered as objects.
Based on my understanding, I think this is another type of workflow. Everything looks correct except when exporting the ADM BWF - The exported file is blank. It does recorded the info of the mix but just without any sound.
So now I'm wondering that is this way a correct workflow? If it is, what is my mistake? I can see that in the export window, the source is called "(My bus name) assign" instead of "Dolby Atmos Send Patching", and is greyed out so I can't change it. Thanks!