Adding more features to the roaming option is still planned, but it is going to be a while.
I assume you mean there are 4 clusters of symbols on the circumference of a circle in their respective quadrants? If you see an actual circle drawn out that would indicate that there is a constant amplitude with the frequency error being too large to decode properly. (symbol phase spinning around on the unit circle). The solution for this would be to make sure the reference frequency is correct.
Thanks for pointing that out. When you see the X, you know that would be a problem area for old style FM demodulation where the symbol decode decision is dependent on the absolute instantaneous phase at symbol time. With the P25RX (and I assume SDS, G4), where quadrature is used (I/Q), the symbol decode decision is the phase change between the previous symbol time and the current symbol time. (relative phase change). This way ,if the absolute instantaneous phase at symbol time moves around as received, the symbols will still be decoded correctly as long as the sync is good. The way CQPSK works is that you have a QPSK constellation (4 dots in quadrants) that is rotated by pi/4 every symbol time. This is what makes the signal compatible with FM demod. If you were to plot the "constellation" of this, it would look like 8 clusters of dots around the unit circle (two QPSK constellations separated by pi/4 rotation).