Hey Vetter, thoses splines look über dry. That may have caused your clutch to not engage/disengage properly which explains the hard feel of the clutch and the grabbing you felt at idle. Obviously that will cause the clutch to glaze, overheat and ruin the whole shebang. Do you have a pic of the input shaft on the gearbox?
Don't sweat the petty things, pet the sweaty things...