Fantastic news, now you can enjoy some good pulls! For my ims competition double, i found 17gms for most coffee seems good, now i start with 17gms and pull 1:1.5 ratio to start with. I am also using the sette, when you make the adjustement it takes about 2-4 shots worth of grind to settle in i found, also amount of beans in the hopper do also have an impact on how the machine grinds i find. I usually put 1.5-2 shots worth of beans to reduce popcorning.
Good Coffee: Technique/Knowledge > Grinder > Beans > Water > Machine