Write permission error during render in 15b8

This one again. But I think I've worked out exact steps to reproduce.

0. Open some project
1. Open Deliver page
2. Go to File Tab
3. Select Filename uses Custom Name
4. Enter some name in the Custom name field
5. Click the Browse button
6. Select a target folder and click Save

Expected Results: Location field should be updated with newly selected location and Filename field should be the Custom name specified in step 4.

Actual results: Once step 6 is completed and the new location is selected, Custom Name is updated to reflect the full absolute path of the file (with front slashes, even though this is on Windows). So if I enter Foobar in step 4 and select F:\Temp in step 6, the Location field is correct but suddenly the Custom name field is updated to be F:/Temp/Foobar.

This causes the render to fail with write permissions error.

Window 10 x64 (1709 build 16299.547), NVIDIA 1080 Ti (391.35), 8700K, 64GB.

Check out here: https://forum.blackmagicdesign.com/viewtopic.php?f=32&t=77437

Check out here: https://forum.blackmagicdesign.com/viewtopic.php?f=32&t=77437

Thanks Josef. I actually did see that thread but assumed the root cause was different because the OP reported his issue fixed with b8. On my first read, it didn't quite sink in that BMD had slipped in a replacement build for b8. Indeed, that new spin of beta 8 does fix this problem.

Cheers!