IMPORTANT UPDATE: see last post instead
Author of bp100 here, I don't think this is related to my mod.
This happens when the mod is enabled on an existing save; peeking at the source, it seems that player data (global.pdata) isn't initialized for existing players during on_init.
Here's a possible fix:
add to on_init (and maybe on_configuration_changed):
for player in game.players do
if global.pdata[player.index] == nil then global.pdata[player.index]={} end
end