Not sure which mod's side this should be addressed on, but I'm reporting it on both.
I get this error when a space platform is destroyed with both this mod and Space platform graveyard enabled:

The mod Space platform graveyard (1.0.3) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event space-platform-graveyard::on_entity_died (ID 4)
The mod Particle Physics (0.1.8) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event particle-physics::on_entity_cloned (ID 135)
__particle-physics__/control.lua:173: attempt to index local 'entity' (a nil value)
stack traceback:
    __particle-physics__/control.lua:173: in function <__particle-physics__/control.lua:170>
stack traceback:
    [C]: in function 'clone_area'
    __space-platform-graveyard__/control.lua:91: in function <__space-platform-graveyard__/control.lua:72>

looks like this mod will need to chance local entity = event_data.entity on line 171 to local entity = event_data.entity or event_data.destination

Thanks for the report. Quezler's suggestion seems right to me, so I used that fix.