Every cast and crew member who isn't a Brazilian resident or doesn't hold a Brazilian passport will need a work visa or a temporary visa to be able to film in Rio de Janeiro, city or state. However, location scouting will only require a tourist visa. For more information about visa issuance or types you should contact your local Brazilian Embassy or Consulate. You can find a list of Brazilian Embassies and Consulates here:
http://www.brasil.gov.br/governo_federal/estrutura/emb_consul/embaixadas/
In some cases the FRRFC will be able to facilitate the issuance of work visas for cast and crew assigned to projects approved for shooting on location in the city or state of Rio. Normally visas are issued by Brazilian Consulates and Embassies abroad. Once eligibility requirements are met, Ancine will issue an authorization letter to the Brazilian producer, which must be presented to the Consulate or Embassy in order for the visa request to be processed.

Foreign producers must establish a partnership with a Brazilian production company, who, in turn, must be registered with Ancine, and who will report to the national agency on the foreign producer’s behalf. In order to be able to shoot in Brazil, one needs to be associated with a local producer and registered with Ancine (National Film Agency). In order to be eligible for incentives offered by Filme Rio-Rio Film Commission (FRRFC) the local producer’s company has to be registered either in the city of Rio or within the state.  

The relevant Brazilian Government Agency for Customs matters is the Secretariat of the Federal Revenue of Brazil (Receita Federal do Brasil - http://www.receita.fazenda.gov.br). You may also request assistance from the RFC. For further information on any of the above questions or for other additional information please contact: rfc@cultura.rj.gov.br.

Two value-added taxes in Brazil: 1) State sales tax (Imposto sobre Circulação de Mercadorias e Serviços [ICMS]) of 17%. However, in São Paulo, Minas Gerais and Paraná the standard rate is 18 percent and Rio de Janeiro is 19 percent. ICMS is due on the physical movement of merchandise Interstate sales has been unified into the single rate of 4 percent for transactions involving imported goods, from 2013.  2) Federal excise tax (Imposto sobre Produtos industrializados [IPI]). IPI excise tax is due, with a few exceptions, on all goods imported or manufactured in Brazil. Rates range from zero to a maximum of 330 percent and average about 10 percent. Luxury goods are at the high end of the tax scale.

There are no government restrictions at any level regarding script content.