You get good translations if you correct your errors.
I beginn with the first sentence:
Was mögen Sie über deinem Heimatland?
first error:
The preposition »über« doesn't fit to the verb »mögen«. In German you don't combine mögen with über but with an:
This is better, but still not good:
Was mögen Sie an deinem Heimatland?
second error:
Du not mix »du« and »Sie« within a sentence when talking to the same person.
Either you use »du«, then you get this:
Was magst du an deinem Heimatland?
Or you use »Sie«:
Was mögen Sie an Ihrem Heimatland?
Both versions are ok.
Let's step to your second sentence
Was hatten Sie von Ihrem Heimatland gefallen?
third error:
Again the wrong preposition. »Von« does not fit to »gefallen«. Again it must be »an«:
Little bit better, but still wrong:
Was hatten Sie an Ihrem Heimatland gefallen?
fourth error:
The person you are talking to is in the wrong case. It must not be nominative (»Sie«) but accusative (»Ihnen«). The sentences subject (which stands in nominative) is the interrogative word »was«. »Sie/Ihnen« is not the subject but an object (here an accusative object).
Another step better, but still wrong:
Was hatten Ihnen an Ihrem Heimatland gefallen?
Fifth error:
Now the auxiliary verb must be corrected. »Hatten« is wrong, it must be »hat«:
Grammatically correct, but still not a correct translation of your sentence:
Was hat Ihnen an Ihrem Heimatland gefallen?
sixth error:
I think this version is among all possible correct sentences the one that is closest to what you did write. But it is in past tense ("What did you like about your home country?"). It should be in presence tense:
Now it is good:
Was gefällt Ihnen an Ihrem Heimatland?
But when talking to a friend or a child you should replace »Sie« by »du«:
Was gefällt dir an deinem Heimatland?
Fazit
This are good and correct translations:
Was magst du an deinem Heimatland? (when talking to a friend or a child)
Was mögen Sie an Ihrem Heimatland? (when talking to an adult stranger)
Was gefällt dir an deinem Heimatland? (when talking to a friend or a child)
Was gefällt Ihnen an Ihrem Heimatland? (when talking to an adult stranger)