When you say 6 speed - is it MT?
Check under the hood for any extra wiring.
I wonder if your car does not have a aftermarket module for remote start.
I do not recall now, but I think SX could also get the OEM remote start module.
Anyway, try that - press lock and right then press trunk release. Just press, no hold.
If yours is MT - I am not sure how it would work for remote start, unless you parked in in N and used handbrake, and the system allows for it...