The only difference of the versions is the variation of transaltion. Translating classical Arabic (fus-ha) into English is not an easy task, and the variations can be abundant; nonetheless, the essence and meaning are pretty much identical.
I read both of the versions; not much difference in translation. The English text, although varying, translated into the same thing in Arabic.
There are two versions because of the nature of the translation, not because a change has occured in the Koranic text.
Remember, translation is an art, not a science.