@d-healey Yup, a bit of noodling with SFZ suggests it's going to be straightforward to write something to create a valid SFZ config file from the asset directory. Lots of subtleties to look into, but basically have something working and will probably knock together a web tool to just take a project stem and generate the appropriate SFZ file.
There is more to the license, but it allows commercial use of the samples but explicitly not the repackaging of the samples into a commercial library (which seems fair enough). https://www.pianobook.co.uk/terms.
Shouldn't cause any issues with providing tools to help create virtual instruments.