Do an experiment, put your camera on the side so you see the breast from the side and then run the slider to max and min and back again while looking at the breast. You will notice that the nipple is in the EXACT same place and never moves outward from the chest when you slide the size up. The size of the breast goes up only sideways and down, which is unnatural and makes the breast look like a flattened pancake.
If the nipple on your screen actually moves forward out from the chest along with the rest of the breast then yea, it might be just on my pc then... maybe its my windows 7, or something idk...
I've played a bit longer now and sometimes it fixes itself, i don't know how or why or when.
I noticed that too, seems It depends on the models.
Use the "possess" option to try characters.
The big space-girl with shades, gets all the weird things you mention. Most likely, she is an older model?
Her tits go weird-wild with the slightlest slider touch.
The main Pocahontas girl also has issues.
I increase her assest because I'm not into skinny girls, and that's when her body might get weird too, specifically his ass (in her case), which actually has a slightly weird shape (sort of like you say, it remains almost flat but increases in wide)
The futanari bunny girl, on the other hand, barely has any issues.
By far she's a much better model. His ass's shape increases well with a slider, same her tits, and general shapes.
Her body giggling is actually beautiful, and I didn't had any strange de-morphing when doing poses. Apparently, if I understand correctly, she's a newer model.
(honestly, I found that girl's model to be much more hot than the main girl)
(note: as I said to someone else, Windows 7 works like shit with Unity/Unreal. I switched to W10 and now I'm having a blast finally trying all the Unity/Unreal games)