I have enough squares finished to make a partial skirt (Yeah... I was an idiot and didn't make enough dye to finish all the squares at once... ) I took that along with me to FIDM to check the color against the real Zam. I was happy.
No, the 3/16" wasn't too loose and in fact, I had to really work at it to get it through the second time. If you've already opened the lace, you could make like a test run, see how it works for you - I just think the 1/8 might be too thin and then be loose in the holes - especially the sides of the skirt where there is only the one strand.