... the colony and carrier ships work fine, but the siege, battleship, and support battleships are not displaying their textures correctly
You colony and carrier ship are not fine... cl texture are rgb in place of rgba... siege-battleship-support are in the good format ( rgba ) but the alpha channel is blank... mean that all the ships surface is team color... if team color was enable in your game setting, the ship in your first pic will not look black but will be green ( team color )...
As dolynick explain , the nm map are wrong ( but not the reason for your dark ship )... cl and da need to be saved in the dxt5 format, nm map in the dxt5n format ( this move copy the red channel to the alpha in a automatic way )...
Finally, none of your .dds have mipmap level ... mean that full texture will always be used, same when your ship is far away and his only a few pixel onscreen...
Next time, when you post a pic for texture problem, enable everything in your game setting ( team color, bloom, etc )... more easy for other to diagnose the problem...
EDIT : your .mesh are wrong too...
TXT
MeshData
hasValidTangents TRUE
...
NumVertices 5166
Vertex
Position [ 19.942768 24.385151 -368.685944 ]
Normal [ -0.000000 0.000000 -1.000000 ]
Tangent [ 0.000000 0.000000 0.000000 ]
Color 0
U0 0.526143
V0 0.839205
U1 0.000000
V1 0.000000
Tangent was not created in xsi... having it on true when tangent are 0,0,0 and U1/V1 are 0,0 will lead to jumping shadow ingame( shadow jump from one poly to a other poly )...
A quick fix is to set "hasvalidTangents" on "FALSE" and replace all the "V1 0.000000" by "V1 1.000000"... so, the GPU will calculate the tangent on the fly... V1=1 simply define the handiness... value need to be -1 for any flipped poly that you have not correct previously...
For a good fix, return to the xsi stage and calculate the tangent and create the secondary UV set for tangent...
As your model have are not bevel on the edge, it is best to recalculate your normal and use angle weighted normal...
Will be best if your learn to segment, unfold UV map and optimize UV map... there is a lot of surface not used on your map, mean that you have less pixel for make high quality paint job... your UV seem to use axial projection who mean that zone who are not facing one of the axis will have some streching artifact...
There is maybe some other problems but for make a full check, i need the model in .obj format...