Day 5 after FUE for hairline (3200 grafts). I see two wide cracks cutting through the transplanted area (Photo

Instead of panicking, it would be best to contact your doctor for a follow up in the office.  Many doctors offer cleaning and washing in their office to help you with the scabbing.

I see nothing alarming from the photos you provide.  I strongly suggest that you accept that it will take 8-12 months to see your final results, that you follow your surgeon's instructions and that you stop reading anonymous Internet opinions that will not change anything and will drive you crazy. 

It is normal for individual scabs to form in the recipient area of a hair transplant. Sometimes these coalesce to form a sheet of dried crusted blood/tissue fluid. Cracks in this crust can occur as in the photos. This should not affect the growth of the transplanted hairs.You should always follow the post op instructions given to you by the doctor who did your surgery. Opinion varies on whether to keep transplanted grafts dry or moist, what products you should use, and when you should start actively trying to remove scabs and crusts. 

What you are seeing is terrible post-operative care which has allowed thick crusts to form on your head and then crack.  An FUE is treated just like a regular hair transplant with regard to the recipient area, but the donor area has open wounds which require daily washing with soap and water. Within 3 days of surgery, you can resume full activities, heavy exercises if you wish. The recipient area requires daily washes as well to keep the recipient area free of crusts. I generally recommend the use of a sponge and supply my patient with a surgical sponge to fill with soapy water and press on the recipient area daily. By repeating this daily, all crusts can be washed off without any fear of losing grafts. IF any crust are present, use a Q tip and dip it into soapy water, and roll it on the crusts and that will lift them off without dislodging them, but never rub them, just roll the Q tip on the recipient crust. I like to see no evidence of any crusting in the recipient area and the crusts from the donor area gone in 7-10 days with daily washing.
I don't like the idea of anyone removing grafts that have scabs on them because we have published a paper in a formal medical journal, that when a person pulls off a scab (crust) from a recipient area in less than 12 days, the risk of losing the graft is very high. Put a shampoo on your head and let it sit for 10-15 minutes, then gently work the crusts with your fingers. This will take days to get the crust off so that you do not disturb the grafts.