1) Yet in Beta, there seem to be the singals, who build blocks, dunno how they’re called right now, the only ones, a classic variant from the steam era and a modern one with 2 aspects.
2) I think both, they’ll deliver such basic things like multiplayer, if they add multiplayer, for free and things like new trains, maps etc. as payable DLC.
3) It really is only a maybe, nothing definite planned.
4) 1 Ingame Day = 3 Reallife-Seconds (On normal gamespeed |> so, one Ingame year = 18 Minutes 15 Seconds RL-Time)
5) Dunno, I’m not a beta tester, trust stonelouse’s answer
6) Dunno, but I guess yes, since the devs create the game as modfriendly as possible, there are alrdy mods now in Closed Beta.