1) A T-Pose is NOT required in frame 1! Frame one is not shown by SL when the animation is played, but all it does is allow SL to know which joints will play the animation When it is played in Second Life. It does this by in the following way:
Any joint that is NOT the same between frame 1 and frame 2
is included in the animation. For example:
Suppose you want to make a pose of an avatar carrying a teddy bear in her right arm, but you want the avatar to walk and fly and move her head when you move the cursor.
1) Create a 2 frame animation of you holding the bear with both arms.
2) make sure that frame 1 and frame2 are idendical
3) Go to frame 1 and change all the vectors for the left and right
arms that hold the bear to <0.0, 0.0, 0.0>.
The arms will look like the T-Pose.
4) Save the animation as a .BVH file and
If you don;t want typing to override the holding
upload the animation at Priority 3
If you DO want typing to override the holding animation
Upload the animation at priortiy 2
Set the looping checkbox and set the start looping
valued at 100% and ending at 100%
Set a suitable initiation time. I like .70 secs,
but this is a matter of taste.
When you play the animation - the default animations of SL will over-ride everything except the right arm and the avatar will carry teddy around all day without dropping him or going wacko when you type, if you have set the priority at level 3.
Now suppose you want to Tickle teddy every once in a while with you left hand. To do this you want to over-ride the carrying animation with a tickle animation:
5) Create a second animation of your tickling action.
6) Make sure frames 1 and 2 are identical
7) Go to Frame 1 and change all the joints of the left arm to some other value. This allows SL to know that the only thing that should happen differently when you initiate Tickle, is the left arm will go into action, but the rest of the avatar will do whatever it is already doing.
Save the animation as a .BVH file and upload the new Animaition set the priority. It must be equal or higher than the holding animation. so:If you want typing to override the left arm - Priority 2
If you want typing to NOT override the arm - Priority 3
DO NOT CHECK the looping box - you want the tickle to play once and then stop.
Set a suitable initiation time.
9) Play the holding animation - the avatar will raise its right and left arms to hold the bear and stay there.
10) Play the tickling animation. If everything is working, the left hand should break out of the holding pose, tickle the bear and then when the ticling is over, will return to the holding position.
using these techniques, you can create many useful animations and overlay animations to be used with SL avatars.
Hope this is helpful