Your hardness is set at 40 grains per gallon (that's pretty hard water).
Bypass the softener, run the cold water for several minutes so you get a
good sample of unsoftened water, collect the water in a clean container and
head down to Sears. They'll test your water for hardness and either give or
sell you a new manual.
Lime looking deposits suggest that your water softener isn't always
working, too much time between regenerations probably. But this should be
obvious by taste. Once you get the manual read up on cleaning the screen and
other maintenance things. And set the hardness to reflect the new test
result if it exceeds 40