ID 253309 - Empty folders in export preset structures are converted to file entry's in Nuke Studio 10.5v1 after reload

Problem summary
Empty folders in export preset structures are converted to file entry's in Nuke Studio 10.5v1 after reload

Customer reported version
nuke.10.5v1

Customer reported platform

Steps to reproduce

1. Open Nuke Studio 10.5v1
2. Add clip to timeline
3. Go to export window
4. Create preset with empty folders
5. Save Studio project
6. Open Studio 10.5v1
7. Go to export window and look at preset with empty folders
Result: empty folders have been converted to empty file entries

Workaround
Unknown. 

Reproduced by support
Can repro issue:
OSX 10.11.3
Nuke Studio 10.5v1

Windows 8:
Nuke Studio 10.5v1

Folders maintain empty in:
OSX 10.11.3
Nuke Studio 10.0v5

Expected behaviour
Expected export preset to retain empty folders like in 10.0v5

Actual behaviour
Empty folders have been converted to empty file entries