The Kia edition (Primo 2.0) worked on devices with 32MB of RAM, it's not a memory problem.

You were also a little bit lucky in the setup, because that device is not designed to activate the GPS receiver via the dedicated driver (port splitter for Primo)
But there is something characteristic about it so that Primo does not support it.
We know that the exe file must support a certain device configuration, and this is mostly the case with almost all igo variants, for almost all devices on the market. But, there are cases where some edition of Primo works better with a specific device than others.
Obviously, there is something with that Navigon that is not compatible with Primo at all.

I already forgot about that iGO variant (the so-called Primo 2.2) that was really the most universal for a while, you don't have to worry about its stability

I will update/change the topic title a little bit latter according to the discussion we had

Edit: done