What should my guide track contain for you to record the drums to?
Your track can be as simple or as complicate as you like.
Preferred : full band backing track. If you would like Goran to be aware of all the parts in the song and play according to what is happening in the music, then getting him to record last is the way to go. This way he will be able to interact with or stay out of the way of individual instrumental parts, as if he was playing with a full band in a live situation. This is the way you will benefit the most from Goran's musicality and musicianship.
Optional : You can also submit a track as simple as a rhythm guitar and voice recorded along the click track. In this case you would need to give Goran further written instructions since there wouldn't be much musical information to feed off.