Starting Point Vimsottari Dasa

So he wants you to start the sun dasa at ardra nakshatra instead at Krittika. So you find the difference from krittika to ardra which is 40 degrees as you did. 

Take the selected ayanamsa for 1/1/2000 and find the ayanamsa in kala jataka on that day. add or subtract (my brain is to tired today to figure out which  you need to do, so just try it and see what works) 40 degrees from that number. Negatives you subtract from 360. Then go to custom ayanamsa, put that value in the box with reference date 1/1/2000

thank you so much, ernst!