The first time the trigger executes, it functions properly but the second time it triggers, Indigo sends an Off command to the Insteon switch. Here's the log when I execute the trigger twice in a row:
Trigger Kitchen lights on low if motion dark
Sent INSTEON "Kitchen Sink" on to 100
Schedule Kitchen lights on low if motion dark (delayed action)
Sent Hue Lights "HUE Kitchen Sink" on to 15 at ramp rate 0.0 sec.
Trigger Kitchen lights on low if motion dark
Sent INSTEON "Kitchen Sink" on to 0
Schedule Kitchen lights on low if motion dark (delayed action)
Sent Hue Lights "HUE Kitchen Sink" on to 15 at ramp rate 0.0 sec.
The Indigo trigger is not set to "toggle" but to "turn on." Below are screen shots. The is no "off" trigger that turns off this light if the motion sensor turns off, so this seems to happen if the motion sensor changes from on to off and back to on, sending the Trigger's Insteon ON command to a switch that is already On.