Thank you all for the helpful tips. The link to jford's article was particularly helpful and also highlighted the overall problem that I originally posted about.
The BiaB manual is very dense with lots of very useful information about song creation features. In the distant past I think the reference section contained much more information about how BiaB itself works behind the scenes in order to produce the outcomes for all its features.
Jford’s article demonstrates what BiaB does behind the scenes to play and audio demonstration of a midi stryle when the Demo button in the Stylepicker is clicked. I was aware of the behaviour BiaB when the same file name is used with wmv files, but I wasn’t aware of how this could work with the clicking of the Demo button, especially the fact that the filename with the same name as the midi style file, but with a wma extension, would cause BiaB to search in specific folder and play this file. I’m sure there are many more features that users could take advantage of in their own work if these mechanisms were provided in the reference of the manual.
The Songs folder can be searched recursively and so there is a great opportunity organise the user song library to best effect. The Styles folder does not operate this way and so there is a single folder into which everything is lumped.
It may be that all of this information is contained in the manual (I’m not the best at finding these things), if so then I apologise for complaining unnecessarily.