Cannot get started with node.js sample

I have a newly installed pi3 with node.js 9.9.0 and npm 5.6.0. I created a groove directory and installed the node-grovepi package using:
npm install node-grovepi

I also ran the quick install command:
curl -kL dexterindustries.com/update_grovepi | bash

It seems to all be installed correctly, but I don't quite get it working. When trying the analog light for instance, I keep getting the same value (~20.0), but it makes no difference if I cover the sensor or hold it up to the light. If I put the sensor on a different port I get different readings (~0.01). So it seems like it can read the sensor but are not getting the right values.

If I try the leds nothing happends, not even an error...

var led = new GrovePi.sensors.DigitalOutput(2);
board = new GrovePi.board({...});
led.turnOn();

Appreciate any help ;)

Reproduce the analog light and LED examples with node.js 9.9.0, npm 5.6.0, and the node-grovepi package after running the listed quick-install command. Start by checking the node-grovepi sensor entry points and DigitalOutput usage; done means identifying the cause of the unchanged readings and inactive LED, or documenting the required correction.