Sorry for the late answer, we were on a training.
I take a look at it
Could this be a compatibility issue with the new version of WordPress?
No, I don’t think so. I will take a look at it.
Go to WordPress admin -> Appearance -> Theme Options -> Body -> Typographie and change the color for the text. Thats a global color for all text within your website. If you want to have another font color fot the footer, go to … -> Theme Options -> Footer -> Typographie and change the font color for this section.
4: That’s strange! This could be an error made by the big WordPress update. I will take a look at it.
5: These are not icons, these are little images. You can find the images in your theme folder in “images” folder.