I assume that base should be primed prior to installation? This particular base is being installed in a basement and the floor is a finished/layer concrete. If it's not primed the raw edge would be up against (or nearly against) the concrete which seems like a future problem. Any advice?

Also, we are trying to avoid shoe mold since we want a more modern, clean look. Any advice on how to install the base as tight as possible knowing that the cement floor is likely not perfectly level?

Thank you