Hello, the mod causes other players to be unable to connect to a multiplayer game until they restart their client. The issue appears to be that the mod_storage of a player is nil within the get_is_modified_flag method called by the on_player_changed_position method at line 118 when the player first joins.

Hello, thanks for posting!

Just to make it clear get_is_modified_flag is called on line 116, not 118. So unless there's a typo please let me know if it's not a 0.1.5 version.
Another point, as I've been facing similar issue during development, it only reproduced when hosting player moved. So, could you please also confirm that players were "unable to connect" instead of were "dropped because of the observed mod issue"?

The fix is probably trivial but I need to understand what is the condition here that was missed for mod_storage initialization. Could you please provide some more details on your server setup and player activity connection wise? For example: * How many players were in the game? * Was it host and play or running headless server? * Were there player drops / re-joins before the issue occurred?

I've found the issue. The crash happens if an already connected player is moving while a new player is joining the game.

Workaround: already connected players must stay still when a new player is connecting until they have joined. As soon as they join, the "on_player_joined_game" event handler will initialize "mod_storage" for all of the players.

I'll try fixing it, but now it may not be as trivial as I first thought! XD

Fixed issue in v.0.1.6 for cases when players are not actively benefitting from the mod, i.e. when not boosted with belt immunity.

I'll investigate further if it's possible to avoid desyncing when joining but for now I'd label it as a known limitation with the workaround being all players on the server must not run along the belts with working belt immunity equipment while a new player is connecting.

Should be properly fixed in 0.1.7.