Select the rotation format to use. The ACL plugin supports three rotation formats: Quat Full Bit Rate, Quat Drop W Full Bit Rate, and Quat Drop W Variable Bit Rate. The Quat Drop W Variable Bit Rate option is almost always the best choice which is why they are set as the defaults. The Quat Full Bit Rate, and Quat Drop W Full Bit Rate options can be used as a safety fallback and for debugging purposes. You can select a format from the following options, using the drop down-menu: Quat Full Bit Rate: Compressed data to 32 bits floats, which essentially retains raw animation data. Quat Drop W Full Bit Rate: Compresses data to X, Y, and Z 32 bit floats and drops quanterion (W). Quat Drop W Variable Bit Rate: Compresses data using a variable bit rate to store X, Y, and Z data, dropping the quanterion (W). The variable bit rate is the ideal choice and the other option is provided for debugging purposes.