Whilst an easy, quick answer was available for BookWise, the question still begs asking for those for whom no solution exists: is there a way to make adjustments to the default product type?

My shop features products to download: both freebies and eventually for-sale items. They fall under a variety of categories and product types: some are designed as specific to particular 3D product that the client has already purchased, some are more generic enhancements and refinements, such as textures and tubes (2D solutions).
What I'm hoping for is to eliminate the need to add a new product type by modifying the music one to suit my needs. I'd like to modify the product type admin page - the handler page for music is "product_music", but it seems that this name is not so much a single php file but rather references a folder in:
/store/admin/includes/modules/
which contains a number of files. Am I to assume from this that all of the files contained in this folder would need to be modded in order to develop this new product type?

I don't think I've hijacked this thread - I found it looking for a more flexible answer than simply downloading an existing template. A humble thanks to any Zen expert that replies...
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