omro,
I'm sorry, but I don't know what white plastic things you are talking about--can you send pictures?
There are only the four corners, the case front and back, and the grey plastic frame that everything is attached to. If you can't send pics, refer to the pictures earlier in the thread, and describe what you mean.
I'll check back.
Kent Walters
P.S.
The covers for the cap sense buttons don't need to be removed, and are best left in place; I would put them back on.
KW