AFAIK there is currently no Portuguese translation. Instructions are here
and there's a general thread about the issues here
. If you find you can't translate certain bits its because the code has not been prepared for translation of that bit yet. When you're done contribute the .po file here please.
The actual marks are part of the CMAP data set, you won't be able to do those.
You may be able to purchase
some more up to date CMAP files online or from a vendor as these are still updated. Just make sure they are version 93/2 as later ones won't work