Given a travel related situation, and given a specific question about the situation, summarize the question into a title

[EX Q]: I'll be going to France for 4 months to conduct research towards my PhD. I believe I will be issued with a long stay visa for research to cover my trip. I have the required "Convention d'Accueil" from the organisation I'll be spending time at. I currently hold an Australian passport.

My question is, is this research visa considered a "Type D", like the other French long stay visas and does it allow entry into other Schengen areas? Does the research visa carry any specific conditions (besides the fact that you need a "Convention d'Accueil" to apply)? 

I will have a month off during my 4 month stay, during which I'd like to travel around to other countries, hopefully I can do this with the one visa.

[EX A]: Does a French long stay research visa differ from a regular "Type-D" visa and are there implications for travelling in Schengen areas?

[EX Q]: What happens if I leave Moldova through Transinstria? I guess I won't get a Moldavan exit stamp, would that be a problem if I visit Moldova again? Wouldn't it look like I overstayed in the country illegally?

[EX A]: Can I leave Moldova through Transnistria?

[EX Q]: Is it possible to buy (western quality) disposable nappies (diapers) in Costa Rica and/or Panama?

In Costa Rica we are planning to be in: La Fortuna, Monteverde, Montezuma, Manuel Antonio
In Panama: Boquete, Bocas del Torro, Panama City

[EX A]:
Nappies (diapers) and baby wipes in Panama and Costa Rica