I don't havethat machine but I don't hoop anything but stabilizer on any of my projects. For things that can be washed I use a patch of iron on stabilizer on the back of the item and then use wash-awat sticky stabilizer in the hoop and then I baste it down too. For things that can't be washed I use the applicable stabilizer in the hoop (and/or on the item) and then spray glue to stick it down and then I baste it down too.

You don't say what type of fabric you were trying to put that big number of stitches on or what stabilizer(s) you used - if you add that perhaps others can give you suggestions.

Before tightening your hoop do you try to smooth out the fabric in the corners of the hoop?
Are you making sure not to stretch the fabric and stabilzer when you hoop?
When you wrap the inside hoop are you wraping the corners too?

Our hoops are the tightest in the corners and not as tight on the long sides and the top and bottom sides.

Any movment of fabric and stabilizers occurs from the sides and top and bottom of the hoop when we embroider.
The needle movement into and out of the fabric and stabilizer pulls on the fabric etc. and pulls it onto the middle of the hoop.
This can really throw the design off.

So if you wrap your hoop don't wrap the corners as this just forces the long sides and top and bottom out more and they will be even looser.

I use strips of Shelf Liner and adhere the strips to the bottom on the inner hoop with a 2 sided, water soluble tape called Wonder Tape.

There is a picture on the Criswell K-Lace website showing where and how to place the Wonder Tape and Shelf Liner strips on the bottom of the inner hoop.
You will notice that the tape and shelf liner is on the four sides but not into the corners.
It also shows Badgemaster hooped and how the strips of shelf liner looks like when the Badgemaster stabilizer is hooped.
This works to hold any fabric and stabilizer taut/tight in the hoop while embroidering and really eliminates the movement of the fabric etc.

You can click on each picture to see a close look at each picture.
Link is below.

The Wonder Tape can be found in the notions section of most fabric or quilting stores and the Shelf Liner can be found in Dolloar stores or stores such as Walmart in the closet organizing section or Kitchen section and it comes on a roll.

You can leave this on your hoops and just change the tape and strips when the strips look worn down. The Wonder tape will wash off as it is water soluble.
I have had this on my hoops for a long time and have not changed it yet.
I found that I don't have to tighten my hoops so much when the strips are on so it is easier on the screw that tighens the hoop.

EastWitch2

Perhaps you are using too many layers of stabilizer.
What fabric and stabilizer were you using?

"Never adjust the screw on the hoop after hooping your fabric with the stabilizer. This action will cause the fabric to shift in the hoop and ultimately be another reason for puckering of the fabric around designs."

Further hooping guidelines can be found at The Flying Needle.

I have two Bernina 180's I've had my original one since they came out. I NEVER hoop my fabric...only the stabilizer. I use spray adhesive, double back tape and a basting stitch. I've done upwards of 90,000 stitch designs and they look great.

Here's a photo of one of my designs using a combination of spray adhesive, basting stitch and double back tape. You can also use a washable glue stick. This design is around 6" X 8" and I think it had around 40,000 stitches. Looks good doesn't it?

Muffy :)

After you have your stablizer and fabric hooped tightly, pop them out of the hoop without loosening the hoop. Then pop them back in the hoop. This redistributes the fabric and keeps it from being bunched up around where you first tightened the hoop.

Were you using a Tear Away stabilizer or a Cut Away?
Seems to me 1 layer of a medium weight Cut Away 2 or 2.5 ounce Cut Away should hold that many stitches.
Or you could try 2 layers of Fusible No Show Mesh cut away stabilizer fused to the fabric and then float a layer or tear away under the hoop when you begin to stitch. This wouldn't be bulky to hoop as the no show mesh it light weight.
What fabric were you stitching on? Does it have any stretch to it.
If it does that could put your design off too.

Penny
I just read your comment about you using the polyester fabric.
You said the Tear Away buckled badly by the end of the design.

I think using a Medium weight Cut Away or 2 layers of Fusible No Show Mesh cut away fused to the back of the fabric and then floating a layer or 2 of medium weight Tear Away under your hoop when you start to stitch the design may work better for you.

Fusible No Show Mesh Cut Away stabilizer is light weight and will not add bulk to the design or to the fabric and when on your fabric would be less bulky to hoop.

Usually with any fabric that has stretch to it would be a good idea to use some type of Cut Away Stabilizer.

The Tear Away buckles because it can not hold and support that many stitches.

I don't understand why you are using solvy water soluble on the top of the fabric?
Your fabric doesn't have any nap and really you should be all right stitching right on the fabric with out it.

Solvy is usually used on napped fabric such as towels or knit type fabrics such as T-Shirts to hold the nap down so the stitches don't sink into the nap while stitching.
Eastwitch2

I am sorry to hear that you still have so many problems. I never hoop the stabiliser with my towels. I only hoop the towel with wash away topping and then float the stabiliser at the bottom. Never had problems with it that way. Hope this might help somewhat.