What is your calcium level at? The recommend range is 250ppm to 300ppm.

Calcium is extremely important in the curing process of the plaster. If it is to low then the water will start to eat the calcium out of the plaster and you will end up with a rough surface.

Typically you would check the fill water for the level of calcium before you fill the pool. That way you can make the adjustments while the pool is filling.

I've never heard of calcium cracking marcite. if the calcium is to high it can stain the pool by leaving calcium deposits on it.

You should be checking, recording and monitoring all chemical levels. Calcium hardness, total alkalinity and pH. Also the pool must be brushed thoroughly twice each day for two weeks. The plaster dust on the surface must be vacuumed to waste. A vinyl vac head is best to use to prevent the surface from getting marked up from the concrete vac head wheels.

Hold off on adding chlorine unless absolutely necessary.

Calcium hardness should max out at 400 PPM. 350 PPM a good level. A sequestering agent is good to add to prevent scale buildup. Pre-dissolve the calcium in a bucket of pool water and distribute it evenly around the pool in the small amounts.

Creating cracks from adding calcium is pure bunk. Not having enough calcium will the cause the water to pull any calcium in the plaster out creating real damage. The plaster contractor is stupid. Maintaining calcium hardness levels on new plaster is a known factor for many years.

The plaster takes 28 days to fully cure. The first two weeks managing are paramount.

It's possible that your fill water has high calcium which may be why your pool builder said not to add more. If you add calcium under these circumstances, you will get scaling. The builder may have tried to scare you into not adding any to prevent call backs because of scaling. But as the above poster said, calcium cracking the plaster is baloney.

Check your calcium hardness immediately, if you haven't already. The calcium hardness will increase as the plaster (marcite) cures but you shouldn't let it stay low for too long. If it's been more than a month since the pool was replastered, the damage may already have been done, If it's under 250, you need to add calcium.