I'll be using this thread to keep track of railways that need tunnel work and which ones are completed. Feel free to do the same and join in the fun of getting these finished:
Aether Line: All tunnels complete. Track broken at Belthil - switches you to the wrong side and then sends you backwards. Pending repairs.
Cerelia Line: FULTON JUNCTION IS BUSTED - sends you back the way you came. Tunnels complete from FULFWOTZ to LOST. CLEMENTINE underground needs lighting. Both 'FOUND' STATIONS are incomplete. Transition to underground in FOUND is unfinished. Transition underground past KALDARON is unfinished. *CERELIA LINE IS SEVERED HERE!* Lines are good from MODAORA to RIVERWOOD.
East Shire Transit: Line still under construction
Dulcia: Rail around DUOMO could use some attention. Otherwise, Dulcia is COMPLETE.
Empire: All tunnels complete. Tunnel between SAGUARIA and PALUSTRIS is a good remodel opportunity. [Line is unfinished].
Franco: Appears to be primarily a rail line in theory only. Good service to Lythia from New Venice.
Hestia: All tunnels complete.
Juris: All tunnels complete. Potential remodel opportunities between Knavobuki and Woodstock. Woodstock station is barren.
Lamia: All tunnels complete and whoever did them did a great job.
Mainland Metro: Complete.
Nysa: All tunnels between HAVANA and ABERDEEN need work, along with bridges. ABERDEEN tunnels are messy. All complete after ABERDEEN to HYRULE. Tunnels good to VENICE. Second Leg from HYRULE to VALASHU: There is no station at ASPERTIA. Also, there is no ASPERTIA. Otherwise, all tunnels on second leg are COMPLETE.
Quintus: All tunnels complete between GONG-CHENGSHI and SEABRIAR. SEABRIAR Station is not finished. Lots of remodel potential with tunnel between HEARTHSTONE and SEABRIAR. All remaining tunnels from SEABRIAR COMPLETE.
Skira: Remodel potential w/ tunnel between ACADIE and ATHITICA. Tunnel leaving KELIMANJARO toward PHASMA is unfinished.
Thule: Still under construction.
West Shire Rail: All tunnels complete
Zelos: All tunnels complete.