Issues, Problems and Bugs with Adobe Premiere Pro v13
We, at istockplus.com are Adobe Community Professionals (ACPs) and from our experience recently on the forums with users suffering from crashes and weird behavior from Premiere Pro 2019, the solution to most cases starts with checking your system requirements:
then checking the Important GPU Acceleration with Apple Metal and CUDA released by Adobe prior to the release of Premiere Pro v13 (2019): https://theblog.adobe.com/important-information-on-gpu-acc…/
and finally, if Premiere Pro v13 (2019) is crashing and if you have any Logitech Cameras installed, uninstall them with their drivers permanently, Adobe Engineers know about this now and working to fix this issue for Logitech users.
there is an issue with Alpha channels when using Maximum Bit Depth, which is currently under investigation.
If you go to Sequence Settings, make sure Maximum Bit Depth is unchecked. When you go to Export, also make sure Render at Maximum Depth is unchecked. If both of these options are unchecked, the Alpha channel should work as expected.
If that is not the case for you, please let us know your steps to reproduce and the type of file with Alpha (Photoshop .psd, DNxHD .mov, Targa Sequence, etc.). If possible, it would also be helpful if you could supply us with sample file(s) with Alpha that reproduce the issue.