This is an old problem that I never bothered reporting before but, I thought I'd give it a mention in hopes that it gets fixed for 3.0

Using the artwork downloader, the highlighter for the image selection uses an auto-generated colour and works fine
unless you are using <element id="UseArtworkBorders">true</element> and
<element id="Controls.ArtworkFrame" bdr="xxx,xxx,xxx,xxx"/>
then the selection bar colour is overridden by the bdr colour.
Sometimes the bg colour of the panel and the bdr colour are very hard to tell apart.
On that downloader panel, MB is also generating a border colour for the artwork images.
This colour is not effected by "Controls.ArtworkFrame"
Could MB be changed so that is uses that colour for both the border and the selection highlight as well?