Dear S|KH Ji,
Now, let us take, for example, his much debated visit to Mecca. It is reported that during his sojourn in Mecca, one day he stretched his feet towards the "Ka'bah", the House of God. On the objection of some Muslims that the feet must not be directed to the House of God, Guru Nanak is reported to have said that his feet might be turned in any direction they desired. The keepers of the House turned his feet in the opposite direction but, lo! the House also turned around and followed the feet of the Guru. Muslim and many non-Sikh scholars reject this and other similar stories, obviously for different reasons.
However, there is no reason for anyone to be disturbed if this or other stories fail to satisfy the requirements necessary for scientific and objective study. In fact, such stories, whosoever its main character may be, should not necessarily be taken literally. They are basically meant for teaching people certain realities of life. For example, the above mentioned travelogue of Guru Nanak seems to have been narrated to hammer into people's head the idea of the omnipresence of God.
Bhul Chuk Maaf Karni Ji