"Do you like playing the guitar?"
Translation:Gitar çalmayı seviyor musun?
"gitarı çalmayı sevdin mi" - Is that OK or is it strictly for past tense? The reason I ask is that I notice quite often, Turkish uses past tense for liking things that in English we would use present tense. If you see what I'm getting at?
Your observation is true. But you would use the past tense when you see that someone recently started to play guitar and you ask them about their experience so far.
sevdin mi? -> about experience
seviyor musun? / sever misin? -> in general