Twotogo, I noticed another installation error in the picture of the "stress" crack to the left of your window. There is no horizontal Z flashing installed above the window trim and the siding is caulked directly to the trim. If you refer to the installation instructions from any fiber cement siding manufacturer, they instruct that horizontal flashing must be installed in these areas and that the installer leave an "uncaulked" 1/4" gap where the siding meets the flashing. The flashing is to prevent the possibility of water infiltration and the gap is meant to act as an escape for any water or moisture that might get behind the siding. If the gap is caulked (with or without flashing), moisture can get trapped in these areas and cause problems down the road. The fact that I didn't see any flashing above the window indicates you will most certainly have leakage issues at some point. Short of pulling the siding above all windows and properly installing horizontal Z flashing, the only thing you can do is very closely and frequently monitor those caulked joints to minimize water infiltration. From everything I've read and seen on your siding, I have to agree that it is an installation issue. Hopefully you have Tyvek installed behind the siding to prevent rotting to your wall sheathing should you experience water infiltration. Best of luck to you

We hired a contractor to reface our entire concrete porch, including the flush brick trim and steps, in Pennsylavania Gray Flagstone. Assuming you don't want to do anything that drastic---you might be able to use concrete patch on the crack then repaint as brickeyee suggested. There are specific paint formulas just for concrete.

I would use a standard hypertufa mix or use premixed concrete (don’t try to make your own unless you are familiar with the chemistry and points of making a good strong mix). Do not get quick Crete like they use for post holes. That works well because it’s in the ground and rain and water keep it damp as it cures. Remember first, concrete never stops curing. It sets up etc and can be used like driveways after at least a week two weeks better. But even then you keep it covered and misted each day — the longer it stays damp (damp not wet in the beginning) the stronger it will be. But the faster you try to dry and cure it, the more cracks, and more brittle it will be. I see people out there doing DIY walks etc and they got fans going cause they want to use that day or the next — and they wonder why it’s cracked, chipping up on the edges, and spalling in a few months. The way I use to do hypertufa (for lightness of weight) or regular concrete if I needed it to stay in place ie wildlife not messing with them - was to make them up, unmold, and then immediately mist, wrap in double layers of heavy plastic and leave sitting in the shade (no sun) for a few days, check it each day and mist it down daily and cover it back up. Do this for 4-5 days. Uncover and let sit in the shade for 6-8 months and mist it down daily .when it rains obviously no need like in the winter. By following spring or summer - put in big tub etc of water and let soak. Change the water every day x 3 or more if you can. Check water with a pH meter. When it reaches around 6-7 you can plant anything you want except for blueberries they want pH around 4-5 I believe. You are trying to neutralize the lime or the pH out of the pot. Concrete is around12-13 (highly alkaline). Even hypertufa is high because it’s peat and concrete but not quite as bad as straight concrete. Peat Moss is about 3-4 pH (very acidic) and it will bring down the concrete some. And this is how we do hypertufa too. But if the pH is still around 8 then you will need to make sure what you put in it can stand that high a pH - not a lot of choices. Remember 7 is neutral, under is acidic, over is alkaline. Roses like 6-6.5, tomatoes 5.5-6, beans like snaps like 6.5-7+ a little. Asparagus like 7 maybe +. Lilacs like higher 6.5-7.5, Cactus can take higher 7+, but there are lots of pH plant charts. Your potting mixes will be acidic based (peat Moss, and bark) but they initially charge all potting mixes with lime to bring them to a general pH. You can contact whoever’s brand you use (look the manufacturer on the internet, they all have customer service)call them up and ask. They will all be different and different mixes within the same manufacturer line may be different if made for different types of plants. A general mix would be 6-6.5 or 5.5-6.5. You can do a media pour-through test - search “media pour thru pH testing) so you know for sure. But the initial lime charge only lasts about 4-6 months depending on how often you water or it rains. You need to resweeten the soil each year — it depends on the size of the pot. Or you can retest with pour through technique to know what the level is. Regular Lime adds calcium, dolomite lime adds magnesium and calcium. If the pH is okay and you want to add calcium - use gypsum. I just know that mine will need it so I add a tablespoons every 6 months for pots 6-10” and up it for larger. If the pot is deep, you will need more or less. For things like tomatoes I add gypsum because they like calcium and you won’t get cat faced or blossom end rot. But back to the pots. I wouldn’t plant in them for at least 6-8 months or at least through your rainy season, and 3-5 days soaking and changing the water daily. If you don’t change the water, you aren’t getting rid of the lime. Check the pH and dilute with water til it reaches 7-7.3 and sprinkle your lawn with the soaking water — it will like the higher pH.

I repaired a cracked toilet tank (crack was on the bottom of the tank) using that liquid rubber roofing and the mesh that is used w/ the roofing material. (The white stuff intended for mobile home roofing repair.) The repair is inside the tank so out of sight. That was probably at least 10 years ago; the repair is still holding. (I have also used the mobile home roof stuff to get more life out of dishwasher racks that a just beginning to rust. In that use, the material lasted close to two years in a dishwasher that was run daily.) So, I would try that approach on the bottom of the sink where it won't be seen. Or open the crack w/ a Dremel on the inside of the bowl and use hydraulic cement. Doing both would be best--hydraulic cement to keep the water out of the crack to keep pressure off the roofing membrane w/ the membrane as a second dam for insurance. But, it's likely that just the cement will do the job.