In then CodeStyle UI under the blank lines tab, when you change things the preview is not updated.
Also when you reformat a class, the blank line preferences are not honored, in particular the "blank lines around class". No matter what I do i cannot get idea to put a space between my class definiation line and the first field.
See the attached screenshot, i have selected 4 lines around "class", but it does not update the preview, nor does it acutally work when you reformat code.