UPDATE: We believe we've isolated the problem described above and fixed it. I've uploaded a new version. Please re-download. Thanks.
Thanks for the fix but it appears now that the computer units also gain the ability. I played the ship challenge after downloading the newest version and I was wiped out by a sub sending about 200 torpedos my way.
Also, I cannot get Infinite Health to work on any units, but maybe that's just me.