WOW!  You really start off BIG!  LOL

First of all, breaking thread can have multiple causes.  The first thing I want to say is - - -  don't buy cheap thread.  Saving a dollar and having your project go bad can and does happen.  If you can get Madeira in your area, do so.  If not, it is available here but it takes a day or two to get it and your time line may be a problem.   Occasionally, placing a little spray of silicon on your thread may help.  That silicon is found in the vehicle parts department at Target, etc.  Spray (not saturate) the whole spool and let it dry (it takes about 1 minute or two).  Never spray your machine with silicon!  The dried silicon will make the thread a little more 'giving.'  When it is no longer visible on the thread, it MAY be a little less prone to breakage but no guarantees.

I also like Hemmingworth and Sulky.  Stay away from Coats and Clark (sorry) but it is just not a quality embroidery thread. 

Stay away from tear away stabilizer for this project.  Tear away is a less reliable stabilizer than cutaway.  Tear away is better for projects that do not need a lot of stabilizer, like denim.  Your sash is delicate and needs more strength from the stabilizer. 

ALL projects must have a 'test sew out.'  That means to use a similar (or same) fabric and stabilizer and thread with your design.  You will find any problems before you start your project.  Test, then test again until you are happy with the results. 

I am going to recommend that you do some reading. . . . . We are all learning throughout our machine embroidery (ME) career.  You are not alone.  We all had to learn these principles through reading or projects that did not have satisfactory results.  Consider your reading time to be time well spent because it will make your projects much better.

First read:  PE700II Instructions.   This is new and here for you to learn your machine from the ground up.  The PE700 and PE700II are very similar but the PE700II is more computerized. 

Next read:  The Avid Embroiderer Stabilizer Blog  This is a guideline to learn about stabilizers.  It is an overall overview of stabilizers for quick reference.  Eventually, I will be doing a more indepth stabilizer blog, but for now, this will get you started.

Next read:  The Avid Embroiderer Needles Blog  This will acquaint you with needles and their uses. 

I recommend that you read all my blogs, not because they are mine, but because they have a lot of general and good information to help new as well as experienced ME users.

Place a photo here in the forum to help us see what is happening and for suggestions from all the talented and caring ME community here at ATG.  To post a photo of your project, reply to my post and select the Media Icon (film strip in the center area of the screen) and follow the prompts.