Good job...

1. JCT-Green Lane_Tmn Greenview-a is a single 'one-way' lane. At the traffic light you either turn left or right. [ <RL> ]
Correct
2. JCT-Green Lane_Tmn Greenview-b allows only through pass at the junction. 3 go-straight-only lanes. [ ^; ^; ^ ]
Correct
3. JCT-Green Lane_Tmn Greenview-c: left-most lane goes left (probably voice will say "bear left") and the 2 other lanes go straight. [ \L; ^; ^ ]
Correct
Observations:
1. Junction POI is located on the road leading to the junction, but not at the junction itself.
Good observation. The POIs are placed on the road leading into the junction for clarity
2. At the junction, you cannot route into Jalan Taman Greenwood from Green Lane, because it is a 'one-way', i.e. No-Entry from Green Lane.
You're right, the section near the traffic lights on Jln Taman Greenview is a one way street
Let find time to write a guide to standardize the codes and symbols.
