Wayne, You can create two short programs thru ISY to accomplish this. This is what I use:
Program ThermostatUp:
IF CONTROL 'REMOTELINC - 5' IS SWITCH ON
THEN SET 'Thermostat' Setpoint up 1°
Program ThermostatDown:
IF CONTROL 'REMOTELINC - 5' IS SWITCH OFF
THEN SET 'Thermostat' Setpoint down 1°