While I am not privy to your communications with anyone, you do indicate that they clearly stated that it would need to be tested - it sounds like there was a lack of communication perhaps on both ends and followup on your part to ask how it could be tested. We are not here to argue about who did or didn't say or do what however. Perhaps everyone can learn from this miscommunications on both ends. However, that leaves you with a machine that you need help with. You indicate that you wanted it to use it for a number of projects, and from your first post, it sounds like that they all do not include this glitter fabric. Is that correct? What other projects/types of media did you want to use it with? Perhaps, it would be good to try some of those other projects/media while you wait to get this sorted. This is an excellent machine that can do a great many things when one takes the time to learn the process and the ins and outs of it throughly. I would suggest that you try to see if someone can do some test cuts with this media since it is not one that I have seen, nor one I have seen anyone else trying to cut. I am willing to give it a try if need be. It is hard to make suggestions without knowing the media and it is possible unfortunately, that it is a media that cannot be cut with a drag blade cutter. However, having it tested is probably your best bet in figuring it out at this point.
You have noted that you have done some test cuts, with different blades, different heights, etc., but you do not tell us exactly what is the issue other then your followup to Gigi's initial questions to say that you tried to cut with the glitter side down but the mat was not sticky enough so you ordered a new stickier mat. Was the media not sticking to the mat the only issue you had so far? If so, then I would wait on the new mat and blade and possibly try again. You will want conservative settings as far as speed for sure. I do understand your frustration, I have been there but with time and effort the machine can be mastered and turn out some beautiful projects with the right media.
As far as the freezer paper method Gigi referred to, you sandwich the media between freezer paper to give it some more stability then what it would have otherwise.
(Edited to add - Gigi and I posted at the same time so I need to review what she posted.
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