De nada, Frank. Hablo un pocinto de espanol :) . Guess you need a spanish speaking computer to make it look right though LOL.
Yes, the little clear cups do have 3 or 4 holes in them just below the peat pots. I think you can see them if you look closely at the second pic. I used a syringe type medicine dropper to water them. One of those large turkey/meat injectors from Wally World might work even better (hold more water per load).
Not really sure what the yarn is made of. It feels like one of those with some polyester or nylon in it. Maybe a cotton blend. I imagine this would make some difference. But maybe just the open, loose, weave is more of a factor than the type of fabric. Just haven't fully experimented with that yet.
Whatever the material, this one just happened to work very well.
I may stick to using my covered aquarium on my more valuable cuttings. But I will experiment without the humidity chamber on some cuttings I have a lot of.