Well, about Makkah meaning center, it is not meant to be taken literally, this is what I found in Google, "noun. Also Mek·ka; Mak·kah [mak-kuh, -kah] . a city in and the capital of Hejaz, in westerm Saudi Arabia: birthplace of Muhammad; spiritual center of Islam. (often lowercase) any place that many people visit or hope to visit: The president's birthplace is a mecca for his admirers." However, someone told me that makkah is the literal center of the Earth and the Kabah is the extreme center of the Earth. Well, I guess he was wrong.
Ali