I can answer your last question. It does not.
Thanks for this. The manual says:
“The boiler has a connection for an Intergas outdoor sensor. The outdoor sensor must be used in combination with an on/off or OpenTherm room thermostat.
In principle, any on/off or OpenTherm room thermostat can be combined with an Intergas outdoor sensor. With an on/ off thermostat, the boiler will adjust the flow temperature according to the set heating line. With an OpenTherm thermostat, this determines the influence on the flow temperature.”
This implies there is no conflict but it does not say if the Evohome Panel will take account of the sensor or ignore it. I suppose suck it and see. But then I may never know!
I can answer your last question. It does not.