"It is possible by doing the same method used by the Night Elf and Undead buildings even for Human and Orcs. First find a building which is about the right size and shape as the building you want to add the animation to then extract the model to your new model's folder and rename it to something like OrcBirthLarge.mdx for instance also you should convert this model to mdl and make sure that the only sequence it has is birth, birth attachments seem to use the first listed sequence so it's important it is the birth one.
Then in the model (convert to mdl) you're adding it to add a new attachment point called "BirthLink" (not sure if the name matters) and set it's path to the path of your extracted model. you will have to correct the pivots for the new attachment though.
Last things to do in your model (Goblin shipyard in this case) is add a 60 second sequence up the top for the birth anim called guess what, birth. I recomend copying one from an existing model with a birth anim and then correcting the numbers but the important thing is that is is still 60 secs, handily one of the features of the TFT world editor shows you how long an animation is but I'm afraid it's guess and check.
Ok last thing you do in this model is go back to the attachment "BirthLink" and set it so it's only visible during the birth animation and the other GEOSETS are not. You may want to experiment with making the building appear near the end of the build process but I'd suggest sticking with it appearing at the end to start with.
Now you should have a build animation that works but it will most likely still have parts of the original building you borrowed the birth animation from appearing during the animation."
Xaran Alamas