Ixemul.library v49.17 from sourceforge is known to be disfunctional and it should not be used by anyone.
I don't know anything about v50.0, i haven't tried yet.
Version 48.3 is actually compiled by the same person who compiled the Aminet version of 7zip and it should work flawlessly. It works fine on my system! I don't know why it crashes on yours. Have you tried to increase the stack? Perhaps this is just what it needs to work.
