If I may. Since we appear as if we know a bit about tuner drivers I would like to suggest an idea.
I have the os mio4K. Used OpenATV for the longest time. Eventually installing ver. 7.
Currently running ViX 6.4. Versus 6.3 is seems to start a bit slow. Hanging a bit on 35 on the display before muddling to operation.
I also have TNAP installed in a slot. I don't use it much. ViX is what I now use all of the time.

In blindscans for the USA I noticed some missed transponders with ViX. Narrowing my scanning ranges helped a bit. But sometimes not.
TNAP hit them every time. Speaking of closely spaced tp frequencies.
I got curious and placed the TNAP tuner drivers in ViX and re-scanned the problem satellites. The issues were solved. So that is now "how I roll".
Just because the image is tweaked for N. America doesn't particularly mean it won't work for other regions. And the tuner drivers were directly developed to address closely spaced transponders and such.