Maybe it's just that I'm not that good at dousing a traditionally rigged symmetrical spinnaker, let alone one used as a gennaker.
When we doused the spinnaker the last time we used it this summer it went all wrong. .....
Dousing is quite straightforward as long as you follow some key procedures:
Head into a deep broad reach
Ease the guy/pole to the forestay, at the same time someone has to grab the sheet above the lifelines.
With the pole already at the forestay release the guy completely (all turns off the winch, let it 'blow' - the sail will collapse in the lee of the main.)
Pull the sheet into the boat, grab the clew and pull the entire foot of the sail towards you, ending up with it and both bottom corners in hand. By now the sail is a collapsed 'tube' behind the main.(on some boats easing the halyard a few feet only at this time helps)
With the bulk of the foot now in hand, now release and ease the halyard at a speed that the douser can keep up with. Pull the sail in under the boom and into the companionway, or cockpit sole if a dodger is in the way. Whoever's hauling cloth has to move quickly and watch for sailcloth going over the side... whoever's on the halyard has to watch and pace the halyard so as not to get too far ahead of the drop.
Once the sail is down, unclip all the lines and clean up before starting any engine/gear.
In really light air you can do a similar thing directly into the bag on the foredeck, but it needs to be almost too light to fly.