Depending upon exactly what you want to do...
There is a REALLY simple way.
It involves hitting stuff with bricks.
Let's say you want an Elf wearing X clothing parts with X head, etc. (Same procedure applies to any phenotype, obviously).
Take an Elf from stock (any one of the standard NPCs ought to do). Using notepad, exchange all parts you want to alter with the pheno clothing parts, head, etc that you want for your statue. Remember to rename the new parts to match the original "head_g" etc, just to make sure your Elf is all correctly linked together and doesn't become a freakish giblet heap.
Rename it "Statue X" or whatever and set supermodel to "NULL" in Notepad.
Import into gmax WITHOUT animations.
Using "rotate" and "move", tug their arms, legs, head, neck, etc about until the mangy little weirdo is arranged in the pose you want them. With the NPC parts named as per the original model, you'll find that if you rotate, for example, an upper arm, parented parts - the lower arm and hand - will follow. (As a default). Then move the lower arm, then the hand, same with neck then head, legs down to feet. You can get more or less any pose you want (in a blocky, NWN, low-poly sort of way.) Easy enough to create multi-figural statue dioramas the same way. Pose each separate figure roughly, then put them all in the same scene and arrange as required (to put a rider on a mount, for example, or two gladiators locked in a fruitless struggle). Equally you can clone and add, say, extra arms or whatever you need, as I did with those Tantric Statues in the Kali Hak...
I find this method of just hitting the model with bricks a lot quicker than poking about through key frames which may not give me the stupidly strange pose I want anyway. Again, the Tantric Statues I did, aside from having six arms, were seated cross-legged waving their arms about weirdly in a way no BioWare animation would match, so sometimes this method is about the ONLY one.
Once you've got your statue posed, delete all the irrelevant nodes for holding weapons and anything else a Placeable won't need. Obviously if you want a weapon in a statue's hand, you just hit a weapon model with a brick and nail it on in the relevant place.
I then tend to parent all the geometry to the Aurora base... Be sure to make certain everything's parented to SOMETHING anyway.
If the geometry's fairly simple and low-poly, I tend to then attach all the meshes into one piece - if I'm going to just give it a single stone texture.
Obviously if you want textures with more details for individual parts, overlaying a stone texture over the PLTs of the parts involved, you will want to leave the parts separate.
Then just nail it firmly to whatever dais, podium, base, outrageously large watermelon that you want it standing on and you're done.