First off, I'm glad you brought this over to GM help.
Now, that screenshot isn't very helpful to us because that's not the gun you're using in game. I think the rotation depends on your exporter settings. Torque uses Z as the up/down axis, so if you align the gun with the Z axis being up/down, make sure you check the box in the exporter that says use Z as up/down axis. Otherwise, it's axis Y.
The other issue could be the mountpoint. If your mountpoint is rotated, it'll cause the gun to be rotated in your hand. That's probably the issue. Rotate your mountpoint, that should fix it.