ok, I tried it…
And: it works within the picamera environment, I am getting 4046 x 3040 px, with a frame rate of 5.5 fps.
However… - I do not display the images via the HDMI-port of the Raspi, instead I am streaming them for display and storage to a WIN10-client. That is, by the way, the usual approach for film scanners based on Raspberry Pi hardware.
In my experiment, the Raspi is pumping between 70 - 80 Mbit/s over the LAN. You might want to look at @dgalland’s approach, he’s hosting his code at github and entertains also a google-group were you might find help. There are other people who released their source code on the internet as well, you might want to try out their code.
Now, the Raspberry Pi foundation’s camera forum might actually be a better place to ask for support in this regard. If you do so, make sure you are also a little bit more specific when asking your questions, like what kind of software you are using, what your setup is (like how many GPU-memory you are allocating etc) and what the error messages are. Otherwise one can only guess what the problem is.
My wild guess is that your problem might have something to do with the huge frame size you are requesting and possibly insufficient buffer (graphic memory) allocated for that size. If you force in addition the Pi to output a full desktop to your screen (which I think you do), something might not have enough memory space to survive. But I am no Raspi hardware expert, so I am just guessing.
By the way: ask yourself whether you really need such a huge resolution. Certainly such a resolution is an absolute overkill if you are working with Super-8 or similar small formats.
Anyway, operating the HQ camera with the picamera-library at 4046 x 3040 px is possible.