Well, if you're not worried about having a ton of clouds everywhere, you can do the same thing in the .cap I posted but change scrollxleft and stuff to the edges of the layout. That way cloud repositioning won't be affected by your player's current position.
If you really want to use a tiled background object, just use this:
Always: Set cloud value 'scrollspeed' to 'scrollspeed' - n*timedelta
Set cloud offset to self.value('scrollspeed'), 0
Just make sure the cloud uses a pow2 texture.