hmm .. wait until Stief gets here, he might have a word of advice.

I've had same problems of LW 4.16 not running as I suggested, but I changed Java settings & deleted LW prefs to solve the issue. Java settings might mean just one movement in position of java version ... or more ... so play around with it in meantime.

The fact you had another account work fine with LW 5 is a major plus. Even I was unable to achieve that. I had to install OSX afresh on a different drive. Thus I need to reboot into that drive in order to use LW 5.

BTW Java settings as for which version is higher or lower is account specific.