Verified answer

The first use of 就 is not correct. The second use is ok. 就 means 'then'. It is meant for something that follows something else. He did this, and then I did that. If he did this (as in your example), then I will do that.

所以 is part of the complement of 因为. Because he did this, so I did that.

For example, 因为她没穿衣服, 所以我杀了医生.

The first å°± means "just" because, so the translation of the first sentence should be "If this doctor killed a woman just beacause she didn't dress up".

You should not use 所以 because the sentence is not written as "that's why I'm going to kill this doctor!" The translation of 就 of the 2nd sentence is "then", or "in that case".

First, it should be: 如果这个医生杀了一个女人因为她没穿衣服的话，我就要去杀了这个医生! The first 就 isn't needed. And, it's quite difficult to explain, but 所以 more closely means "so", so then the sentence would mean "...so I would want to kill this doctor." However, by using 就, it would (roughly) translate as "...I will [want to] kill this doctor."

For your main question, I'm not sure I can explain it; it's complicated. Sorry.