Creating a station
First prepare all your music files, talks, commercials etc. and don't forget to convert them to *.ogg files.
Start the CSL Music Mod Station Editor and insert the name of your station, give it a description and a thumbnail. The description will be seen in the content manager when you publish your station to the Steam Workshop. The name & thumbnail are of course used within the selection of available radio station during the game.
Collections are a great way to organize your songs and are later the #1 way to play songs only at certain situations. So plan ahead and create the collections you will later need. Please don't forget that the collections are global. Name them so they clearly belong to your station. You can also add collections from other radio stations & vanilla collections that are accessible within the arrow menu next to Add.
The next step will be to add the songs by editing the collections. But first you have to save the station. Pick some empty folder and save the station into it. You can add *.ogg songs by using the Add button or by dragging the files into the list. The editor will then copy the songs into the correct folder. You can also set the content type (music, talk, commercial, ...) within the editor that will rename the song file accordingly. All operations are just file operations. If you don't want to use the editor, you can just copy & rename the files using your file manager.
If you are using collections from other stations, you of course don't need to add songs. But if you do, they will be added to the list of existing songs - using this way you can extend other radio stations.
If you want, you can create a custom schedule. Cities: Skylines will cycle through it from top to bottom.
The contexts feature allows to set up rules in the form of Play songs from collections x, y and z if A and B or C. The mod will go from top to bottom and use the rule that applies first.
If for example you want specific songs play when it is raining and other songs if it is night, you make a rule for rainy weather and a rule for night time. This on the other hand would leave out the case if it is raining and night. Adding a rule with higher priority compared to the more generic cases then also cover the special case. To summarize use can use a general rule: The more specific, the higher the priority
Create your rules with Add context, give them a name and set the collections that play if the rule applies. In the next step, you will setup the mechanics that explain to the mod what you actually want.
Keep in mind that if no rule applies, the station will just play all songs. If you don't want this, create a context with the lowest priority that will act as default context. This default context will requires no special circumstances when it will be active, so skip the following steps for it.
If you edit a context, you can access the available and the applying conditions. The available conditions ask the game for example if it is night time or if the citizens are happy. The other setting connects those measurements together to give an answer if the rule applies.
First, the available conditions have to be set up. There are different condition types available. Choose the appropriate one, give it a name & set the parameters accordingly. If you for example want to know if it is night, create a time condition from 8-20.
Note: The list of available conditions is global within the station
CSL Music Mod allows you to connect the available conditions together to allow more complex rules like Play those collections if it is sunny or there is a firestorm disaster or it's rainy and rainbows are visible. The applying conditions allow you to create such more complex rules.
By default only an Add button is visible. Click it and create it creates a box. Click it again to create more boxes. Each box works as a group of available conditions that must apply at the same time. The whole context applies if the mod finds such a box where all conditions apply. In other words, the conditions within a box are connected with an AND while the boxes are connected with an OR.
The summary will show you the rules that must apply for the context to be played.
To test the station or just have it for personal use, choose Tools > Export to local mod folder. This will create a music pack mod ready to use & publish within Cities: Skylines. If you want to update your mod or just export to a different folder, use File > Export music pack.