1. Is there a ban on donations from foreign interests to political parties?

Article 19, Decree-law of 2011-87,2011, of the organization of political parties:
Political parties are prohibited from accepting:- Direct or indirect financing, in cash or kind, issued by any foreign entity.

Article 80, organic law 2014-16, 26th May 2014, of elections and referendum:
It is prohibited to finance the campaign through foreign sources, including governments, individuals, or legal entities. Money that takes the form of a donation, gift, cash, in-kind, or advertising grant from a foreign source is considered foreign financing according to tax legislation, regardless of the nationality of the financier.

Unofficial English translation.

Political parties are prohibited from accepting direct or indirect financing, cash, or in kind from a foreign source.