After a second look, she is right. You left out a set of curly braces. Here's mine:
${color}CPU: ${alignr}${cpu}%
Here's yours:
CPU usage:$alignr${cpu cpu0}%
Yours should be:
CPU usage:${alignr}${cpu cpu0}%
See if that works. If not, try:
CPU usage:${alignr}${cpu0 cpu1}%
I can't remember the syntax for displaying more than one CPU.