Hi,
Most probably you are confused with directory selection dialog. Neutron does not use Android's music database but builds own. When you are offered to select directories you need to select those which may contain your music files. Selection is done by activating pin-button on the right side of panel with directory name. Then by pressing DONE button you are activating database build procedure. After it is completed you will notice music entries sorted by categories. I hope this guide helps.
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