Map Sitinjau Lauik V17 has been completed and officially released. for ETS2 v 1.36-1.54
For more instructions read the attached readme in the link.
Update for V16.1 this among others:
1. Addition of 4600 km of the new route covers 7 cities; Rantauprapat, Aek Kanopan, Kisaran, Indrapura, Tebing Tinggi, Lubuk Pakam, Medan
2. Adjustment of the length of the Panyabungan-Samosir and Pekanbaru-KotaPinang route
3. A few details additions and fixes

Credits:
Lamtorogame