Ive been trying to get my new races ears into the tes constructer but whenever I try to change the current ears to my new ears it says invalid directory. My ear file is a NIF file. Do I have to put my new ear mesh in the Oblivion-Meshes.bsa file? If so How do I get it in there? Someone please help!

No, it doesn't go in the bsa. If you're creating a new race you should create a new folder within your Data/Meshes/Characters directory and name it whatever your new race is then drop the nif in there, then in the CS navigate to that folder to pick it. Ears also need egm and egt related files in the same folder.

Does the TES Construction Kit crash because It only has the nif file but it needs an egm and egt file as well?