I can assure you that I DO have the latest MLA. The directory called "USB Stack" is used in several example projects that I found that use composite USB devices together with the USB framework.
So why (TF) are you concentrating on that meaningless trivial fact when there is so much wrong with the USB framework that really needs tidying up and making useable ?
If you want to say the microchip example projects in MLA do not use that directory so other people are at fault, so what ?
Are you saying that all the projects in MLA are complete and a text book example of clarity and good coding practice ?
No, well then maybe, just maybe, instead of focusing on something no one cares about, how about you do something useful ?
If you want to help, fantastic, please do something useful like sort out the USB framework. Or at least point me in the direction of an example project of a USB keyboard and mouse device that actually builds with Mplab-X !