SLU

[CCR]

This is not uncommon even with an experienced installer. Light grinding is fastest and you don't need to "blend" the ridges into surrounding areas in order to achieve a nice flat surface for the floor covering.

As far as pinholes, that is typically a result of the K15 being installed over a highly absorbant slab, resulting in the mix water being sucked out of the K15 too fast. Did they prime the concrete with P-51 Primer as required? Highly absorbant concrete needs to be "double primed" with P-51. Prime with P-51 mixed with 3 parts water, dry for an hour or so, then prime 1:1 with water (normal mix ratio), before installing the K-15.