@shaun-pillai, if I understand correctly, you probably need to:

Install curl from here.

Add a TRIGGERcmd command called GarageLightsOn that runs this command:

curl http://192.168.0.101:3480/port_3480/data_request?id=lu_action&output_format=json&serviceId=urn:micasaverde-com:serviceId:HomeAutomationGateway1&action=RunScene&SceneNum=57

Setup your IFTTT Webhook with these settings:
Method: POST
Content Type: application/x-www-form-urlencoded
Body: token=(your token from the instructions page)
URL: https://www.triggercmd.com/api/IFTTT?trigger=GarageLightsOn&computer=ComputerName