Would appreciate a list of easy to follow, step by step instructions on how to get styles to appear in the drop down mode found in the TinyMCE editor?
Is it just a case of amending the area in the admin -> config -> system settings -> editor so that it points at a relevant stylesheet, and it will just read through the styles on this stylesheet, and populate the box??
Yes you could do so. You can also change the path in episerver.config, the settings is called uiEditorCssPaths. You can also have an dynamic property and name it EditorCssPaths (I guess).
In your css you can decorate each style rule so it appears in the drop-down.
EditMenuName: Red text;