I’m looking at it right now.
First thing I noticed is everything is set to pivote to the cursor instead
of the median point. That’s easy to change back from the drop down menu.
Or hold Shift and press ‘comma’. (but maybe that wasn’t the issue)
Also, you have all the hip area bones connected to the Master. You’ll
want to keep them children of the master bone, but uncheck the Co
button to keep them disconnected.
Another things I noticed is there isn’t a whole lot of influence coming
from the hip bone. It’s acting like there isn’t even hip at all.
Your model and armature are both way off center in your whole
scene so that might mess things up too…but maybe not. It’s
just better to keep it in the center while building everything.
Parenting from bone heat is ok, but it’s not an end-all solution.
It gets you in the ball park, but you’ll have to go in and edit
all you vertex groups and/or touch things up with manual Weight
Painting. If you check the hip vertex group and click select to
see what vertices are assigned to it, you’ll notice that most of the
vertices of the hip area are assigned to nothing at all.
If you want, I’ll fix your rig a little bit at least to get the hip functioning.
Also check out what I posted here for Vertex Group help: