I think it means that the sewing machine is using a computer that checks if everything is sewn properly like this Durkopp Adler machine:
https://www.duerkopp-adler.com/en/main/products/MS_11_engineered/550-867.html

When I do this, I always first examine how a strong thread was used on both sides of the original cover (sometimes # 40 + # 40, sometimes # 30 + # 40, sometimes # 30 + # 80 ...) and what was the stitch length and I it same.

I have good experience with this type of clips:
http://www.vehicleclips.co.uk/bmw-x6-e71-e72-plastic-trim-clips-for-side-skirts-rocker-cover-mouldings.html

The same type is used in OEM door panels, in your case they will work just as well...why not?

Dynamat is too expensiv, you pay too much for name. In trade exist a lot of similar deadening materials. I (in Europe) use russian STP, it works great (I wrote that russian army use it for their tanks :-D - so itmean that it's tasted for wide range of the temperatures) and price is much much better.
For noise and temperature dampening I use 8-15 mm closed cell foam with self-adhesive layer. It's better than jute. It's very light and work much better.
I use carpets from UK Coverdale whith latex rubber backing. How do you sew 2 pieces of carpet together? I sew them about 1 cm from the edge, but it has happened to me that when I munted it in the place of complicated curvature the surface the seam ripped from the carpet and the carpet split :-( How to prevent this and insure the seam?

Hello Sander,
I have double needle sewing machine... what experience do you have in mind? Do you have some concretely questions?

Jan

I use a transparent plastic foils in which suppliers send me the material - it works well, it's thin so it can be archived in office files ... and it's free, I don't have to buy it anywhere (and I recycle - I save nature ;-) )

where you buy headliner fabric for Porsche? I can't found the right perforated fabric, everybody have perforation for Mercedes which is different :-/

The question is if you want to build your own name and brand or build a joint project tag. I have experience when the joint project has collapsed (not my fault) and all the energy invested in building a common brand was useless and now I have to build my own brand. It's not easy to keep a long-term Brand where you are not the only one owner.