When you create monsters, meteors or visibilities during the game, you always create them for a level precisely. If you didn't take care about levels, everything will be associated to the first level, level number 0.
Once you've finished a level and you want to go to the next level, which doesn't exist yet, here is what you have to do :
Create physically the next level into memory with command "-newLevel" (-newl).
Create the start place of the next level with command "-createStart next" (-crs n). Do two right clicks to form the zone.
Create the end place of the current level with command "-createEnd" (-cre). Do two right clicks to form the zone again. Be sure this zone is not avoidable to reach next level. Don't hesitate to make parts of the zone on the death terrain.
Once the next level created and prepared as explained above, there are two ways to go to this one : finish the current level using the old way or typing command "-endLevel" (-el). All monsters and meteors of the level are removed, which is normal. They appear again if you go back to level 0 with command "-goToLevel 0" (-gotl). But visibility zones stay enabled.
It's possible to modify the start zone of the current level with command "-createStart" (-crs). But for level 0 you have to move region "departLvl 0" in worldeditor itself.
To enable the team to earn some lives when reaching the current level, it's command "-setLivesEarned ‹numberOfLives›" (-setle). If you use it for level 0, the number of lives you will choose will specify the one at the start of game.
You can display a message at the start of the current level too, it's command "-setStartMessage ‹message›" (-setsm). To erase the message, you simple have to type the command again, without parameter this time.
To simply display the message of the current level, you just have to type "-getStartMessage" (-getsm).
You can display the number of levels existing for the moment in the map, by typing command "-nbLevels" (-nbl).
If you create a map with other players, it's possible that each one works on a different level at the same time. If for example you are in level 4 and that teal player wants to modify level 3, he just has to type "-setMakingLevel 3" (-setmkl). Monsters and meteors of level 3 appear then and all modifications teal will do will be applied to that level. When the player will want to make on the current level again, he will type "-setMakingLevel current" (-setmkl c).
At a time to know what level you are making, you can type command "-getMakingLevel" (-getmkl).
The end zone of the last existing level will be the zone of the end of the game. It's sad but once it's reached, the game will restart. Except if you modify the map triggers to create a true end of course.