For example, the way magic works in Thedas. It's mostly by tapping into the Fade right? The land of dreams, of imagination, and magic is just willing that imagination into reality. But here, it's not that simple. If you want something done, you can't just dream it up and have it manifest. You want fire, you have to rub some flint together, or get a match. I think that's primarily what I'm thinking when I say reality is different here than it is in Thedas.
I really think you speak of something else. Maybe you don't understand what I mean because I express myself wrong.
I am not going on about how something materializes. If you like we can assume a mage dreams it into being.
I mean that if the veil were not a physical barrier (as suggested by someone before) this concept would still work. A "Veil is not physical" theory could be like this:
The Fade is like an overlay to the physical world, spirits etc. are always there. Simply another dimension/layer in our space-time continuum. (Here we have Physics to throw in one of the respective theories.)
But these spirits are not able to interact, like we imagine ghosts to be mere observers who might make a bit of noise in an abandoned house but not much more. The reason being (possibly) that the physical creatures are incapable of perceiving the spirits (ghosts) around them in the first place (mental barrier a.k.a. veil), so they will not realize they are there and whatever side effects those spirits cause will be attributed to other occurrences by the ignorant physical beings ("it was just the wind"). (This is where cognitive and neuroscience say hello and take over.)
However, some creatures have a better ability of perceiving this "overlay" because their mental barrier (cognitive filter) is weaker (the veil is thinner, or say, the Force is strong in those ones). They are, hence, able to perceive the Fade, thus allowing interactions with it.
Others wish to be able to do so and use blood magic to weaken the barrier/veil deliberately in order to interact with the Fade. Other story. (And here we have magic waving its hand.)
As a result it does "not matter" is the veil is physical or mental, the result/effect is the same: a few people can interact with the Fade while others cannot. Only the approaches to explaining the reasons are different (one is basically "it's magic", the other being "science can explain") but it does not contradict (or express any idea at all for that matter) the notion of how Fade elements materialize in the physical world (so that also those beings with a stronger mental barrier/cognitive filter/veil can perceive them).
So, what I am saying is that it's basically totally unrelated to what you wrote. I think. And if you still don't see what I'm trying to express I must apologize and attribute it to my inability to express my thoughts and give up because I find no other words to wrap the concept in.