--- You wrote:
way).  Clearly to change it would or could break old orchestras which
is something I am trying to avoid.  I have implemented a rand2, rand2h
and rand2i set of opcodes which use a full 31 bit generator.
But... is that what is needed or would you prefer to see this as an
optional argument to the opcode rather than a new opcode?  Or not at
--- end of quote ---

backwards compatibility is nice, but i prefer to look forwards..

my vote:
make "rand" the 31 bit generator, and have an optional
flag to turn it into old (16-bit?) rng...

this might make old orc/scos sound different, but at least they will still
"render" with no errors