Created attachment 344848 [details]
The main license of the package is found in in COPYING, see attachment. I suggest to add it as licenses/Snd. AFAICS, it is a free software license (very similar to the "tcltk" license) and therefore can be added to the MISC-FREE group.
In addition, all of the following are needed, see notices in individual files: BSD-2, HPND, GPL-2+, LGPL-2.1+, and LGPL-3+ (the latter only for snd-12*).
Unfortunately, files dlocsig.rb (installed with USE=ruby), and dlocsig.scm (installed with USE=s7) contain an additional non-commercial restriction that makes them non-free:
Copyright (c) 92, 93, 94, 98, 99, 2000, 2001 Fernando Lopez Lezcano.
All rights reserved.
Use and copying of this software and preparation of derivative works
based upon this software are permitted and may be copied as long as
no fees or compensation are charged for use, copying, or accessing
this software and all copies of this software include this copyright
notice. Suggestions, comments and bug reports are welcome. Please
address email to: firstname.lastname@example.org
IMHO, "free-noncomm" is a good enough approximation for this.
So in summary, LICENSE should be as follows:
snd-9.11: "Snd BSD-2 HPND GPL-2+ LGPL-2.1+ free-noncomm"
snd-12*: "Snd BSD-2 HPND GPL-2+ LGPL-2.1+ LGPL-3+ ruby? ( free-noncomm ) s7? ( free-noncomm )"