Some layouts may have wider graphics than others and on each one options to adjust may be called differently; if there's something like "The width (in pixels) of the margin for left / right side of journal (under Header)" it may be what you're looking for. At least this can adjust the extent inside which text is shown. (To find in: Customize Journal-theme -> Basic Options / Additional Options (down at the bottom on the customize page)).

For the second it needs to be noted where this is supposed to appear, on the page for notifications and personal messages or somewhere else (first one would be suiting).