Firstly, I'm not sure if the code library you added is correct. Unfortunately, there are some minor issues with the database classification. When adding a device, you need to search for SKY Q in the DVD type. The code library searched by model has numerical commands. We will optimize the process and update the app to address this issue.
For children's codes, do you want them to be automatically entered when opening an activity, or do you have a shortcut key to enter them.
If you need to input it automatically, you can add your child code in the activity edit ->startup settings.
If you need to create a shortcut key, you can create a macro in the activity Activity edit -- keys favorites -- macro, command to add children's codes. If you need to use entity keys for control, you can also use Activity edit - Assign keys for X1 Remote, select a button, and assign the macro command you set