Section Numbering and Face.

[Rem]

I am writing my thesis in LyX and I have to stick to the thesis guidelines of 
Graduate School so here is what I need to do:

Sections should not be bold. I change the face from Layout > Font, but the 
number, i.e. 0.1 remains there and it is in bold. Moreover, I need to have 
the section title in the center (subsections must be left justified). 

Another question is how do I set the page margins? I have tried but it does 
not let me set them. May be I need to try milimeters?

Thanks,

Remzi