"Kati was born in March."

Translation: Kati márciusban született.

[richardkiss]

Is "Kati született márciusban" incorrect or unnatural?

[jsiehler]

It's OK. It is telling the listener a different fact, though, because of what's before the verb. You can probably understand the difference best by considering the questions that would elicit the two different sentences:

Mikor született Kati? Kati márciusban született. (When? In March.)

Ki született márciusban? Kati született márciusban. (Who? Kati.)

[AndrsBrny]

In addition, when the context is more neutral, something like Tell me something about Kati, it is more natural to say Kati márciusban született..

[Nab918927]

So does "született" cover past, present, and future? - "was born", "is born", "will be born"?
"Kat márciusban volt született " was not accepted.

[jzsuzsi]

született is past tense.

past: Kati márciusban született. Kati was born in April.

present: Kati márciusban születik. Kati is born in April.

future: Kati márciusban fog születni. Kati will be born in April.

"volt született" is not used at all

[Tielbert]

in all examples you meant iN April, of course

[jzsuzsi]

oh, thanks

[Tielbert]

as far as i see, szuletett is an active past tense verb, not past participle, so "volt szuletett" is a weird combination.
If I am wrong, plz, correct me