Creating a code component class and marking the UCLASS() macro with meta=(BlueprintSpawnableComponent) does not allow the component to be used inside blueprints.
Adding ClassGroup=( [GroupName]) will make the component show up under the given group name.
1. Open UE4Editor (any 4.7 project)
2. Add code to project based on StaticMeshComponent (NewMeshComponent)
3. In Visual Studio add meta=(BlueprintSpawnableComponent) to the UClass() macro
5. Create new blueprint based on Actor and open it
6. In the Viewport tab, click on Add Component to open the component list
7. Search for NewMesh
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