I get this message, is this a bug? What should I do?

The scenario level caused a non-recoverable error.
Please report this error to the scenario author.

Error while running event level::on_tick (ID 0)
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:114: attempt to index field 'puzzletory-skip-level-count' (a nil value)
stack traceback:
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:114: in function 'recalculate_levels_state'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:64: in function 'init_level'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:96: in function 'handle_first_init'
...a/Roaming/Factorio/temp/currently-playing/puzzletory.lua:1045: in function 'handle_tick_event'
...Data/Roaming/Factorio/temp/currently-playing/control.lua:5: in function <...Data/Roaming/Factorio/temp/currently-playing/control.lua:4>