Here's what I did, in brief:
1. Roll pastry sheets to slightly bigger than the size of a laptop.
2. Spread fig jam over both sheets. Lightly sprinkle castor sugar over the area.
3. Roll up the sheets loosely. Cut each sheet into 6 wheels. Reshape them a little.
4. Sitting them cut-side up, stuff as much dried cranberries inside the wheels (between layers).
5. Top with torn-up pieces of figs from the jam. Do an eggwash on top and around the wheels.
6. Arrange the wheels on baking tray and sprinkle castor sugar over. Bake 25-30 minutes at 400F.
On hindsight, I should have sprinkled the dried cranberries in step 2, after the jam, before the sugar.
I suppose it all turned out well - I managed to finish the jam that's been sitting in the fridge for months (neither of us liked it enough...). Edible mistakes - what more to ask for?