Nice, don't need to worry to much about watering or nutes when they are young in soil, I have three plants growing in soil that I literally just forget about, check them every three days.
The leaf curl may not be a deficiency in the seed, I had a hot couple of days and all my leaves of the plants in my hydro system started to warp and twist a bit like that, I got a fan and put an ice pack in front of it so it was blowing over the canopy, the leaves started to come right again and the new top growth was fine.
Topping is is somewhat easy and if you end up fim (fuck I missed) instead don't worry. As above top on fourth set of leaves, I ended up topping three and fim one, the ones I topped have been few days with little top growth (normal as topping sends the message for the energy to be sent to lower points of the plant) but the one I fim has like three new tops, and that was the one I thought I did a really scraggly job on. Check on youtube for some guides, but avoid the ones that encourage plucking the top off by pulling, not a good idea with small plants, use pinch technique or sterilized scissors.
good luck and nice looking girls, I got the promo from herbies before yours, white widow x skunk#1 , have a darkstar, sage n sour, northern lights and two ice in hydro. Have two ww x skunk #1 and one ice in soil. Good luck with pulling some females. I would recommend vegging out for little longer, doing some lst, topping etc first before 12/12.