Hi Aitor,
Normally when we create a new project with KDS wizard, we don't see "release" and "debug" option. these options exist in some demo code, for example, MQX demo.
If you need it, you need configure it by yourself.
Step 1. Create a new build configuration. Right click on the project name, “Build Configurations”, “Manage…”, “New” to create a new Build Configuration.

step2, if "Debug" is already there, create new for "Release"

step 3. configure each of the configurations in properties.
Have a great day,
Jennie Zhang
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