So i take a look at your site, the bold issue works correctly when i view it in chrome.
For the preview bellow the editor i was wrong if the Editor is loaded in the Modal Dialog the skin.css is not loaded you have to put the import line in the /portals/_default/default.css or /portals/_default/skins/_default/popupskin.css
For the preview bellow the editor i was wrong if the Editor is loaded in the Modal Dialog the skin.css is not loaded you have to put the import line in the /portals/_default/default.css or /portals/_default/skins/_default/popupskin.css
But how do I get this font as the default font in the text area directly when opening editor.Sorry but i couldn't find a way to do that.