Oh, yes, the head bounce and arm jiggle. If you look at the test.xml file in dynbouncer.bin, you will see that they have written that into the file, a hinge on the neck bone and some bounce on the arms. I did not remove that from the file in the custom folder apparently. You would need to remove those three sections and add breastl and breastr sections to the test.xml file.
If you are having problems with the reserializer, you could try opening up a command prompt directed at that folder and run it from the command line. That would give you a look at any error messages that might be generated.
EDIT: Combined three posts into one.
As a followup, I just checked my file and it has only the breastl/r in test.xml in the custom folder, so I am hoping you started with bins.hogg and unpacked the file yourself to get the odd hinge neck and arms.
Or, you haven't actually generated a new dynbouncer.bin. If you just enable the test file in skelinfo.bin, as I have done in the version in my post, and leave dynbouncer.bin untouched, you will get those weird effects.
So if you are working on custom breast jiggle, open the dynbouncer folder in the custom folder and edit the test.xml file to your liking. Save it and open the custom folder. You should be able to click and drag the dynbouncer folder onto the convertresource and it should make a new dynbouncer.bin right in that folder. Copy that and the skelinfo.bin tolocaldata\bin and check your work in game.
And for custom breast size, you need to edit startrekfemalescalegroups.xml to your liking and then drag the scaleinfos folder onto convertresource to generate a new scaleinfos.bin and place that into localdata\bin.
Yes, any folder structure under localdata will need to be created with the manual installs right now.