You could use the 2016 RealTracks with 2015 but there are inconveniences. Dr. Peter Gannon says something here: http://www.pgmusic.com/forums/ubbthreads.php?ubb=showflat&Number=323287&Searchpage=1&Main=47410&Words=realtracks&Search=true#Post323287

Sometimes evolution has new features where the code of the older version cannot handle newer developments. VideoTrack mentioned different Windows versions. I chime in but I'm using a different harmony. In Windows XP you could search for certain properties like title or certain keywords of files. You still can do this in Windows 10, but since Windows Vista you cannot see the respective entries of e.g. pdf-files anymore. Microsoft was wiping out lots of hours of work put in by users worldwide.

While evolution in software almost always make older files useless after one, two or maybe three generations; PGMusic so far establishes a backward compatibility to the oldest files.

If you need an example of bad customer relationship, Microsoft again jumps in as a volunteer. There are features in Access that we used in Access 2000 and could convey to 2003 but no version of Access later than that is able to run the procedures and there is no (!) conversion to newer functions. And to continue, it is no more possible to install Access 2000 on Windows version after XP -- well you can, but you cannot install any other software after Office 2000 is installed. It destroys the UAC.

Updates can be expensive. But often the most expensive update is the one we skip.

Desktop; i7-2600k, 8 GB mem., Win 10 Pro, BIAB 2017; RB 2017 - latest build
Laptop: i5-2410M, 4 GB mem, Win 10 Pro, BIAB 2017; RB 2017 - latest build