i believe (though i havent encountered it myself) that there is a glitch which causes the ghost not to appear when it tell you to go back to him. Not sure how to avoid it or if it's even possible to fix it.
as for the temple of light. go there between 12 noon and 1 PM and you will see the floor all lit up. The donation box is beside the monk standing by the wall (it's a little stone dais, about waist high) and the amount you need to donate is 10,000 + (though for safety I did 10,001)