Being pro LGBT and Christian isn't "perverting the word of God"
Often when conservative Christians argue with more liberal ones on issues such as LGBT, it's common for the latter ones to come up with interpretations that differ from the traditional views and that support the LGBT community, and a lot of those times the conservative side answers with "stop perverting the word of God", "don't be changing scripture for your perversions", "you are twisting the Bible", etc.
But in reality, Christians from all sides have done exactly that since the dawn of time; reinterpret and change their view on different issues and verses.
Things such as: slavery, polygamy, etc. were accepted and condone by the majority of Christians and Jews and by their scriptures and writers for many years, despite most modern western Christians being against those things.
So no, being in favour of Gay marriage isn't twisting scriptures, is just doing what Christians have always done: change.