I have exactly the same issue, the newer versions of OpenBVE doesn't work at all with some NYCTA Routes and trains.
According to your post, you are probably using the v1.5.1.0 which is the worst: lags, blinking textures, white textures, the whole cab was white with only the locked doors indicator and the speedometer showing up as I was loading the R46 on the F, some routes like the B, D, and 6 will crash the game at 50% and come back at the main menu, either showing an error message or sometimes not, Then I tried the v1.5.1.2, it was better: no lags, no blinking textures, no missing textures at all, but still crashes at 50% when loading these routes,except the 6 train that managed to load somehow, but after I downloaded the LisaRaye 2 object pack, didn't load anymore, and still the same problem with the white cab when loading a R40 Slant or other SMEE on the F line, but after several attempts I managed to load proprely the train, the cab was showing up, but then an error message appeared on the top left corner saying that the train plugin could not be loaded, resulting in nonfunctional rollsigns. then I tried the 1.5.512.1319-travis version and the B and D lines succesfully loaded, but everything was missing: tunnels, tracks, except the third rail and the signals. And instead of the white cab, it didn't even show up, I could only see the brake levers, the speedometer display and then the tracks on the F line.
And the v1.4.3 works fine with me as well, but I would love to have the newer versions because it has better features.
