Is it permissible to trim the eyebrows if they become excessively long?
Trimming eyebrows is permissible if they become excessively long, yet; it is reprehensible. And Allah Knows Best.
What is the ruling on storing the meat of sacrificial animals and distributing it throughout the year?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
It is disliked (makruh) to store or preserve the meat of sacrificial animals (udhiyah), whether for a short or long period, provided that the sacrifice is slaughtered within its prescribed lawful time, while also taking care to prevent the meat from spoiling. And Allah Almighty knows best.
Is it permissible for one who sacrifices on behalf of another, with the latter's permission, to eat from the sacrifice?
Praise be to Allah, and peace and blessings be upon our Master, the Messenger of Allah.
It is permissible for one who sacrifices on behalf of another with his permission to eat from the sacrifice with his permission, and he takes his place in distributing its meat.
It is stated in Hashiyat al-Jamal 'ala Sharh al-Minhaj (Vol.5/P.262): 'If a person sacrifices on behalf of a living individual with his permission, does he take the place of that individual in distributing the meat, because permission for the sacrifice implies permission for distribution, or does it depend on explicit permission? There is room for consideration, but the former view is not far-fetched.' And Allah Almighty knows best."
Is Zakah due on the orphan`s money?
Yes, Zakah is due on the money of the orphan.