Repeat Action doesn't work for line spacing

[CAF]

In Word 2010 I cannot get the Repeat Action (F4) to work when changing the spacing before or after a line. In previous versions this worked fine, if I increased the spacing above a line to 6pts, then went to other lines of text I wanted 6pts inserted above, highlighted and pressed F4, then 6pts were added. This used to work whether adding space before or after a line, and for any number of pts. This simply does not work in Word 2010. Any hints as to what I'm doing wrong?