I would like to change the color from white to something darker, since the photos I have used do have a white background and one can not read the "Read More".

Thanks & best regards

Hi there,
therefore you have search the css class for the read more tag and then you can add the found css class to your css/custom.css
Video, how to find the css classes
www.joomlaplates.com/template-customizing

Add this code to your css/csutom.css

.layout-slideshow .sprocket-features-desc {
background:#ff0000;
border: none;
box-shadow: 0;
color: #ffffff;
}

Problem solved.