Hugs editing on Mac.

Dear colleagues, I'm planning to teach a course about Algorithms and Data Structures, by using Hugs. My students have MacIntosh computers (o.s. Mac OS E1-9.1). When I try to use the -E option (with :set or in the Preferences file), I obtain a nice little bomb (rather the equivalent to a bomb in this modern O.S.). What's the problem ? Thank you in advance for your answer. Sincerely yours, JULIO.