Hex Editor XVI32 can do a direct edit to msstyles but usually we don't do it that way.
Reason:If you open mssytles in Hex-editor, a whole bunch of binary data will be presented making it very hard and messy to trace
the right data to edit.( addressing will be difference......)
As for resource editor same thing many don't provide a direct edit... it is more of a resource extractor and compiler to be exact.
Basically these are the resources we need in msstyle editing:
(1). Resource Editor- Restorator 2007( personal preference ), ResHacker, PE Explorer, Resource Builder...etc
(2). Hex-Editor - XVI32( personal preference ), HxD, Hex Workshop ....etc
(3). Photo-Editor - Photoshop ( personal preference ) , Paintshop , paint.net...etc
The only free resource are Reshacker , XVI32, HxD & paint.net
The usual way
Open msstyle in Restorator and extract the image we want to edit, mod it with any of your prefer photo editor
replace it...same goes to the variant file...extract it and use any Hex-Editor to edit the binary data.
This applied especially to the variant file because if you view the address of the variant file from the resource
editor as compare to the extracted variant in Hex-Editor, it will be difference.
If you want to change the explorer background color i think you need to change 2 parts to look good,
the left pane and the right pane ( the big white patch when you open your explorer )
For the left pane the specific address is 2C1E0 and right pane is E188 ( Default for both is FC FC FC )
Note: the address above is only applicable to the usual way
of modding the original MS Aero msstyles....not other way....
also if the variant file is generated from Vista Style Builder ( diff address )
Hope this small info will help ppl along the way.......