Errata:
There is a discrepancy in the number of sts needed to do the first row of the lace for the large size
to fix this
New Row 3:
Inc 1, k12, yo, k1, yo, k37, yo, k1, yo, k12, inc1 = 71 sts this should give you the correct number of sts to start the lace
Purl next row
Now do the old Row 3 ( now row 5)

This top down raglan based shrug is a snip to knit. Start at the neck work down the body and the sleeves and then add the ribbed edging around the opening. Not a seam to be seen!
Revised version now up!
The lace pattern is shown in both charted and written format.

All these measurements are approximate as there is no front to the shrug and the sizes are very forgiving. If you at all unsure as to which size to knit base it on a measurement from shoulder to shoulder across your back
Small: up to 18 inches, Medium: up to 21 inches Large: up to 25 inches

If you are struggling you will find excellent project notes here that may help you.