Okay so I finished my Cammy mod but something was off about her muscles that was bothering me all the time, they didn't looked like her original look. I tried everything from looking at UVs, importing the model again to injecting the original textures but nothing fixed it so after hours of head hitting
I found something really interesting about the normal maps
Apparently a problem is going unnoticed while saving/injecting the normal maps. Take a look at this normal map using UModel
PIC-1 is Cammy's original normal map, now if you extract this using UModel as TGA then open in Photoshop, save it and insert back in UASSET, you'll get below look in modified UASSET.
Notice how the red spectrum have changed into green and green into red in PIC-2. This produces a lot of problems in details, for example
Notice the loss of muscle detail on her arm in PIC-4, also look at the glove. Another example below
Notice her knees and muscles on thighs in PIC-6.
So the problem is for some reason UModel is extracting normal map with red and green channels swapped. You'll have to fix them by swapping red and green ones, blue should remain as it is. How I verified this ? if you open an original normal map UASSET in hex then copy the data from offset 80 to EOF and paste it in a DDS file of same size (Should have 3Dc compression) then you'll get this look in Photoshop.
Now below is the look you get when you open a UModel extracted normal map
Swapping the red and green channels of PIC-8 give you the look of PIC-7 i.e. original normal map, then injecting it back into UASSET gives you the correct look in UModel as shown in PIC-9
I suppose that's also the reason why R.Mika has a weird looking blue shadow below her neck (selection screen) in any mod that has tinkered normal map. I will check this further tomorrow, hope this helps.