Rated 5 out of 5 stars
I tested Corretor para Português de Portugal 188.8.131.52 with SeaMonkey German 2.39 final Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0 from official download area) Gecko/20100101 Firefox/42.0 Build 20151103191810 (Classic Theme) on German WIN7 64bit:
Installation worked fine, without any warning
Function works fine, I tested with a Wikipedia text from <https://pt.wikipedia.org/wiki/Portugal> in HTML Composer, Browser, Chatzilla and E-Mail-Composer, everything looks fine in some formal tests (I do not speak that language).
And support is really great!