I wouldn't describe wax as being crusty and dry. It always looks smooth, blocks the end of the nipple and feels quite solid. Plus if you see wax you should have a foal within 24 to 48 hours or less!
If she is going to wax up then her udder will be full to bursting, probably shiney (skin stretched tight) and teats milk filled to their ends. What she has now on her teats is just a crusty bit of milk secretion - wax looks exactly like candle wax and will 'hang' down from teats to around an inch in length, BUT because it is 'firm' you will often miss seeing it as it breaks off as the mare moves and very often they foal before more wax is formed.
Sweety certainly looks as though she could foal at any minute, but her udder is not yet 'tight' enough to form wax, so dont rely on her waxing before she foals. Mind you she could 'fill' that udder easily in a day or two and then you could get wax before she foals!!
WOW I can't believe you still dont have a foal Jenny!! got onto my brothers laptop today so was able to give a real good checkup of everything!! he definitley has that V
I wonder how different Suzie will look when I get home!! HMMM LOL