source: http://www.facebook.com/credits/
a secure way to buy virtual and digital goods
아이템을 구입하는 안전한 수단입니다
The verb 구입하는 (to buy) doesn’t agree to the subject 크레딧은 since the verb doesn’t take the hidden subject ‘users.’ It must read a 구입할 수 있는 in context. ‘way’ is translated into ‘means/method’, which is not a proper term in context.
Use your credits across any supported games and apps on Facebook.
Facebook 상의 모든 지원되는 게임과 앱에서 크레딧을 사용하세요.
The modifying adjective phrase 모든 지원되는 makes the sentence tone unnatural.
Gift Card
기프트 카드
The more common term 선물 카드 should be used instead of the transliterated term 기프트 카드.
Credits are a safe and secure way to make payments online.
크레딧은 안전하고 보안이 유지되는 온라인 결제 방법입니다
결제 방법 (payments) normally means standard online/offline payment methods. ‘credits’ is not one of the standard methods to pay online so an alternative verb phrase 적립된 크레딧으로 결제할 수 있습니다 would be more appropriate in order to apply the meaning of ‘online money.’
How do I get FB Credits?
크레딧을 얻으려면?
얻으려면 (to get) sounds awkward for online contents. The more common noun 적립 is recommended.
Gift and prepaid cards are also available in retail stores.
기프트와 선물 카드는 매장에서도 구입할 수 있습니다
The translation is not correct. ‘prepaid cards’ reads ‘gift cards’ in translation.
Credits can be used in Facebook games and apps you use on your computer
Facebook 게임과 앱 사용시 이용가능합니다
The connecting word 과 separates the term ‘앱 (apps)’ from the modifying noun Facebook. The meaning misleads the users by implying ‘Facebook games and other apps.’
They are supported in countries and currencies around the world.
전세계의 국가와 통화가 지원됩니다
전세계의 shows a space error. The verb 지원됩니다 (supported) is connected to ‘countries’ and ‘currencies’ in context so the syntax doesn’t sound natural.