After reading a lot I decided to simply try.
My process:
-presoak 1 min in water
-Rodinal 1+100 - 1min agitate, 60min stand development
- usual stop, rapid-fix & wash.

At first I thought it went wrong, as I didn't see any pics...but that was due to the dark orange mask.
Pictures were taken with a ultracheap panoramic focus free camera without exposure measuring with a 1cm diameter plastic lens.
By my 3-year old son
On the cheapest c-41 film I could find locally (no-name ISO 200)
Here are some examples: