I just upgraded to PE15 from PE13 on a Windows 10 OS. The upgrade was to get a better H.264 export with more options.
In PE13 I was able to create an H.264 AVC video in an Quicktime .mov file. The new PE15 version creates two files Test.m4v and Test.wav. I would have expected it to generate 1 file, not 2 files. The m4v file is not recognized when attempting to play it back in Windows media viewer or VLC. The file size is also too small to be a video file.
PE15 was able to create an mp4 file using the "H.264" preset which was playable. But use of the "H,264 AVCHD" preset does not generate a working video.
I also used the Quicktime format Export->Devices->Custom->Format Quicktime and setting video codec to H.264. This generated a workable .mov file but it has the same issues as with version PE13. The H.264 encoder does not have all the control options that are required.
The failing export is done using PE15 Export->Devices->Custom->Format H.264 AVCHD
Premiere Elements version 15.0 (20160905.daily.10366.36)
Running on OS Window 10 Pro Version 1607 OS Build 14393.477
Intel Core i7-4770 CPU 16GB RAM 64-bit OS