Very quickly I found two absurdities that would not be found on the official English UNRWA site, as they try to be very careful in English.
One was the caption for the story, linked to in the front page, for Nakba Day.
It says that "On this day, in 1948, thousands of Palestinians lost their homes, families ... their life, to become refugees."
Really? There was a mass expulsion of hundreds of thousands of Palestinian Arabs on May 15, 1948?
Of course, they chose that day to celebrate the Nakba because it was the first full day of the Jewish state. The Nakba isn't about the creation of refugees but about the failure of the Arab world at large to prevent the creation of Israel and to lose militarily in a war that they all agreed was essential to win.
The second absurdity was this line in that linked article, where it says "Approximately one third of the world's refugee population is Palestinian."
The only reason that this statement can be said is because of...UNRWA! The definition of "Palestinian refugee" is different than "refugee" from any other part of the world, thanks to UNRWA's definition of allowing descendants of refugees to remain in that status forever. Becoming a citizen of another state doesn't chaneg that; living in "Palestine" doesn't change that - they are refugees forever and they keep growing. Since this site is meant to raise money for UNRWA, UNRWA is using their own anomalous definition of refugee to raise more money for UNRWA!
Change the definition to the standard definition of "refugee" used by the UN in every other case, and suddenly the number of Palestine refugees dwindles to perhaps 2% of the five million they claim are refugees.
UNRWA in English is generally sensitive to mistakes like these. Apparently, their Spanish section is not.