3DSMax uses a z-up coordinate system. Unity uses a y-up coordinate system. 3DSMax can export models in a y-up coordinate system. You’d think this fixes things, but Unity ignores this flag and imports all FBX files with a rotation of -90 around the X axis. The models themselves look correct, but the root has a baked in rotation of -90. So if you attach a child to the model, and set its rotation to (0, 0, 0), suddenly it’s rotated 90 degrees. The official “solution” is to set the root to +90X rotation, then build your model’s mesh in a -90X way. But if you’ve made your model without knowing this and made animations, 3DSMax makes this a huge headache to fix (apparently). Etc. All because Unity tries to “fix” the y-up bug.
This has been an open issue with Unity since 2009.
But at least they support Blackberry now.