I wasn't even aware it was supposed to be able to accept .3ds.
Anyway, it's easy enough to convert to Directx, so I wouldn't even bother. The engine will convert to .dbo automatically, which apparently is more efficient. (I know the file size is much smaller, anyway) I think that is where the limitations on polygon/vertex count come into play, is when the .dbo format comes in.
MAME Cab PC: i7 4770@3.4Ghz (passmark 9945), 12GB RAM, Win 8.1/64, GeForce GTX645 (passmark 1898); Shiny new laptop: i7 4800MQ@2.7Ghz (passmark 8586), 16GB RAM, Win 8.1/64, GeForce GTX870M (passmark 3598); Old laptop: i5@2.3Ghz, 8GB RAM, Win 7/64, Intel 3000 graphics