Suggestions aren't cold hard facts.
CAF have delivered a product not fit for service, how is that the fault of TPE? It simply isn't.
CAF will undoubtedly fix the issue in time, but from what I was told (most likely third/fourth hand), this being 2 weeks back too where these issues started to crop up, they're not the best company to work with.
Who loses out? The passenger, oh that's me.
OK then - you are wrong. Cold enough?
You don't seem able to grasp the concepts of quality assurance and quality control. As the customer in these circumstances you do not sit back and wait for the product. This isn't the same as your window analogy. This is a multi million pound investment in new equipment and you seem to think you just fire and forget and then wonder why things go wrong. That is simply preposterous.
As a customer in these situations YOU go out to the manufacturer and asses and audit their processes, procedures and techniques and ensure they meet your standards before you start. You make sure they absolutely understand your specification, the delivery parameters and the acceptance criteria at the start. You then check the build at various stages of the project. You have agents or your own people on site to monitor the build and deal with any change issues that crop up to keep the production line moving and communication flowing. This helps avoid any uncontrolled change to specification or materials used in construction and tries to ensure you get a quality product first time. This is all fairly obvious project management stuff.
If you take your approach you lose the chance to head these issues of early, before they become a delay to delivery.
I do have some experience in exactly this type of thing!