Stop, start, restart, restop, restart.
The multicore RPis do not work well or at all with the PiFM code. Some folks are attempting to fix this. I nthe mean time I have moved the FM section of the project to a less mobile solution but one that works for what I am using it for.
The PiZero seems to run PiFM fine. As I have just one and it is on use on another project it might be a while before I get to reintergrating PiFM into Anyfesto.