>     s blahblah RET
 >     => Says it can't find it, but moves point forward a few characters.

I suppose something like the attached patch should cure that.

 > Go back to the Info directory:
 >     d
 >
 > Search:
 >     s blahblah RET
 >     => Says "Wrong type argument: stringp, nil"

FWIW this happens because in the

	      (with-current-buffer (marker-buffer Info-tag-table-marker)

form `Info-tag-table-marker' is nil and `with-current-buffer' expects
either a valid buffer or a string naming a buffer.  I don't know how
Info tags are handled so I leave this to someone more knowledgeable.

 > That's all.  It was the point moving that I found particularly odd,
 > when searching repeatedly for a term.  First point moved as expected
 > with each "s RET" sequence, but then it carried on moving after there
 > were no more occurrences which was confusing.  I noticed the error
 > after returning to the Info directory following that.

martin