If by "land" you mean "country", then no, it's not wrong. I take it your comment means the course accepts it.
- "God bless America, Land that I love" -- this means country.
Land can also mean realm, domain, or area.
- "Land of Oz"
- The land I bought for my house.
- The land of the living.
These are not generally "lando."
Yes and no. ;) L. L. Zamenhof was an ethnic Jew living in Poland, which was then under the occupation of the Russian Empire.
And so nowadays it’s certainly Poland which takes pride from him being our fellow countryman, applying the term “Polish” in a modern, broader sense. In the times of Zamenhof, where the notion of a “Pole” was very much linked to the specific ethnicity, he didn’t call himself one. Asked about it he wrote:
En la okazo, se Vi nepre bezonas paroli pri mia persono, Vi povas min nomi „filo de pola lando” […], sed ne nomu min „polo” por ke oni ne diru, ke mi — por akcepti honorojn — metis sur min maskon de popolo, al kiu mi ne apartenas.
And here’s my translation:
In case you must talk about me personally, you can call me “a son of the Polish soil” […], but don’t call me “a Pole” so that no-one would say that I — to gain honours — have put on a mask of a people, to which I don’t belong.
EUX is a substitute for EŬ. Esperanto allows for characters that arent in many other languages by recognizing the X as an indication that the previous letter should have an acdent mark. This can be Ŭ,Ĝ,Ŝ,Ĵ,Ĉ,Ĥ. These are different sounds than their unaccented counterparts and if you see the X in Esperanto, that simply indicates an accent mark on the previous letter.
My trouble with "AĵoLerni" or "AĵojLerni" or even "AferojLerni" - beyond the missing accusative - is that before I saw this comment, I (as a long-time Esperanto speaker) always thought it was supposed to mean "learning stuff." That is - the act of learning things. It never even crossed my mind that you were trying to say "AĵojPorLerni". As you said, this is correct.
You could also say Lernendaĵoj.
The country is called Indonezi·o, so the citizen is indonezi·an·o. The adjective is indonezi·a so for example the language is la indonezia lingvo or simply la indonezia for short.
The continent (or the part of the world) is called Azi·o, so the inhabitant is azi·an·o. The adjective is azi·a.
The thing about country names in the Old World vs the New World isn’t really “a rule”, but simply a rule of thumb or an easy mnemonic that works most of the time. :) The real rule at play here is that word roots are to be used sparingly and names for any derived concepts should be formed by applying the rules of the word formation in Esperanto. The secondary rule is to use internationally recognisable words where possible, but with a strong tendency of avoiding homophony.
And so what you’ll find in Esperanto is two categories of country names: ones called after its ethnic group (gentobazaj) and ones whose inhabitants are called after the country (landobazaj). The basic concept is always an indivisible root in Esperanto and the derived concept is formed by adding the appropriate suffix. Since many countries in Europe and Asia came to be as nation states, their names in Esperanto are often in the ethnic-based category. But since the continent of Europe itself doesn’t derive its name from a name of a group of people, but rather the opposite is true — the inhabitants of this continent are called Europeans after the continent they inhabit — the word Eŭropo doesn’t belong to the ethnic-based category.