most of the "specialty" embroidery hooping devices are like fishing lures...designed to catch more fisherman than fish!
If they work at all it is a labor of pain and retrying.
Here are some tips that may help.
Slow the machine down to 400 to 500 rpm for starters.
Use the largest needle like a 80/12 sharp point
Increase your upper and bobbin tension a little more than what you would us for normal flats
MAKE SURE THE SNEAKER IS TIGHTLY HOOPED, NO WRINKLES, SLOP ETC.
MAKE SURE THE UNDERSIDE OF THE SNEAKER IS SITTING SOLIDLY ON THE NEEDLE PLATE
If the item is not a sneaker or sneaker like FORGET IT you can't embroider shoes
JOIN THIS GROUP SWF owners group
https://groups.yahoo.com/neo/groups/SWFOwners/infomooseman