#22\nChange sVpmgp->nrwk from signed int to size_t so that it may successfully deal with numbers greater than ~32k.
For issue #22: One more overflow during memory allocation.  I think I've got all of them now.  Famous last words, right?.
Introduce fixes for memory problems.

r a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
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# the commit.