Firefox 2.0.0.13 crashes, unable to add extensions part one – the problem

I’ve been using Firefox for a few years now, and love it dearly. After the update to version 2.0.0.13, I have experienced the following problems with it:
 

• On one machine, it crashes *constantly*
• I am unable to add extensions (this happens for *all* of my extensions, and I have tested all of them in the same version on another machine)

 
I have tried the troubleshooting tips found in Mozilla’s Knowledgebase, and have not resolved the problems.
 
Am I the only one having these problems?
 
I’ve posted the problems to the Firefox Support Forum, and will post solutions when I find them.