Wish I could help. I've had problems of my own with Excel 2004 (11.4.1) when Spaces is active. Data is not always entered, memory is not released, anything typed from changing column width to font size isn't always recognized.
I recently turned Spaces off, and it seems that the problems have disappeared. Based on a quick read of other threads here, it seems that the problem has not been corrected in Office 2008 either. Is that correct? Based on the above, things might have gotten worse!
Are further updates to 2004 expected now that 2008 is out? But, if they haven't fixed that problem in 2008, seems like the chances of a fix for 2004 are remote, eh?
(I posted the above in another thread yesterday that turned up in a Search. I didn't notice that it was in a somewhat, ahem, inappropriate forum. This is where it "belongs".)