Hello Phil6 and noldo66,
This is Peter Tempel, Support Lead. Please accept Aladdin Systems' most sincere apologies with regard to this bug. We thought it was fixed and it managed to slip through. The workaround you suggest is correct.
Basically, if you have no single quote characters as numerical separators in your OS X International > Numbers preferences, StuffIt Deluxe will not crash.
We intend to fix this issue to allow single quote characters as soon as possible; it is a top priority here. We thank you in advance for your patience and understanding.
Sincerely,
Peter Tempel
Support Lead