I guess maybe i'm dumb (lol) this is only the 2nd car i've owned with CC. My 06 xB has a set/cruise button, a accel/resume button, and an on/off button. My 00' S80 has wierd pictures on it. I figured out the accel button, but I cant seem to get any button to work as 'set'. The top one seems to 'resume' as the last speed i had set, which is what i have to do every time and then use the cruise button to slow down or accel button to speed up to the actual speed i want.

 

The round circle and the 3/4 circle should be the set and resume button.