Not sure about the international spreadsheet (I assume it's the same), but ours has conditional formatting so that when you type in a number (ie: 257), the box automatically fills w/ the color.
I've added rows in between for additional info, and if I recall correctly, I deleted the conditional formatting for them (or else it didn't automatically do it). Or maybe since most is text it doesn't read as a number and try to color it. Also, if doing something like a "+5", if you'll type in an apostrophe first, it will then read that as text, not a numerical application. '+5 instead. The apostrophe does not show up.