I don't have direct experience with this, since I'm expecting to receive my Manchego mould as a birthday gift this month.....however, I have been researching Manchego recipes, and what I've seen is that people have had success using a cloth in the mould, using the mould naked (not sure I'd try this), or going clothless in the final pressing.
I think my plan is going to be to use a cloth in the mould and see how the pattern transfers that way. If I'm not happy through the first press or two, then I'll just go clothless for the final.
I'm really looking forward to using this mould, and wish I could just find some sheep's milk!
HTH,
Rich