How do I make a background seamlessly scrolling?

I tried the tutorial for an infinite scrolling background (https://www.scirra.com/tutorials/4777/h ... und/page-1) but it's not seamless, you can see the background abrutly changing its position. how can I make a bg seamlessly scrolling? I'm using a starfield background.

OddConfection

Here's a working example capx (r244)

It doesn't use Families but is fairly similar to what 99Instances2Go suggested

Perfect example.

You can use the Scroll effect found here:

https://www.scirra.com/forum/effects-by-somebody-neat-things-big-gifs_t123401