I have made the same Russell Hobbs rye bread recipe a few times but it always collapsed and failed. I tweaked it a few times and at last have success. Previously the dough was a little too wet, I slightly decreased the volume of water and added a little flour. I have found that when cakes collapse it is because they have too much rising agent, rising too quickly and then falling before the mixture is baked enough to hold form. The most significant change which I made was to halve the amount of yeast in the recipe. Here is my improved recipe for Rye bread.
Add the ingredients in the listed order and bake on the setting closest to a 500g loaf.
Oil or melted butter 2 Tbsp (30 ml)
Light brown sugar 1 Tbsp (15 ml)
Salt 1 tsp (5 ml)
Caraway seeds 2 tsp (10 ml) (optional)
Strong white flour 200 g
Rye flour 120 g
Dried active yeast 1 tsp (5 ml)
I would like to also mention that during this time while under lockdown thanks to Covid 19 it was hard to find bread flour and I discovered a wonderful South African site for the store The Refillery. I ordered different flours and a host of other dried food items, stocks and spices. Wonderful concept and service. All goods were delivered in recyclable brown paper bags which I decanted into my own containers.