well.i put them in water til the casing cracks,then transfer them to the paper towel for about a day to get a nice root.Some seeds just dont like to germ.My Buddha took almost a week to germ,but my White Rhino,1st day.
cracking time depends on the strain.
were you keeping the paper towel warm..?
put them on top of your hot water heater and that will produce some adequate heat.