You see no soundings on chart US5WA51m.000 because it is quilted with a zoom factor of only 0.25. Zoom in further or untick the SCAMIN setting in the vector tab.
I can't repeat the "going gray" bit, but read
Chart Quilting | Official OpenCPN Homepage, where there is an explanation about when gray areas can appear.
Thomas
PS
It also depends on exactly which chart you have loaded and are quiting.
See below where a few chart are excluded from the quilt.