The chapter in PMEG on capitalization starts out with:
Pri majuskloj (grandaj literoj, ĉefliteroj) kaj minuskloj (malgrandaj
literoj) ne ekzistas devigaj reguloj en Esperanto. Majusklado povas
helpi al klareco, sed estas cetere sufiĉe malgrava afero.
"About uppercase (capital letters) and lowercase (small letters) there aren't obligatory rules in Esperanto. Capitalizing can help with clarity, but is otherwise a rather insignificant matter."
This chapter goes on to say that one does capitalize all proper names, and if a name consists of multiple words, one usually capitalizes each one.
However, if a word is derived from a name, one often retains the capital letter, but can also make it lowercase.
Zamenhof considered the names of months as proper names, and thus capitalized them, but nowadays they are often uncapitalized. Weekdays, on the other hand, are not considered proper names, and are almost always uncapitalized. Names of holidays (Kristnasko, Pasko, Advento) are generally capitalized.
Names of countries are capitalized, but words for ethnicities or nationalities, whether derived from the country name (kanadano, meksikano, brazilano), or having the country name derived from them (ruso, polo, arabo), can be written either way. Same with language names derived from names for lands or peoples. Languages with proper names (Esperanto, Volapuko, Sanskrito), however, are supposed to be capitalized, though some people do write them in lowercase.
I don't see anything about titles in PMEG, but as with the other cases, there seems to be a lot of leeway.