Bueno el otro día salí del paso realizando la animación de nuevo, ya que no solo cambiaba timming si no transformaciones.
De todas formas me encontré con el mismo problema en otro proyecto. Pregunté en XSI Base y me respondieron. Es justo lo que yo necesitaba.
Hi Xuan,
You can use the Sequence Retime tool found in the Animation menu (I am still using xsi 4.2, maybe it has changed name or location -- if you don't find it, look up retiming animation in the online help in the version you are using). Using this method, you can offset, scale or retime animation on marked parameters, a selected object or the entire scene.
If this method does not work well, the dope sheet is just as easy - if you want to retime everything in your scene branch select the scene root, click collapse in the dope sheet, draw a region around the keyframes, middle click on the region handle and drag it to the frame where you want it. In XSI 5.0 and later you can use the timeline as a mini-dopesheet. I think it's the Shift Key that allows you to select a range of keyframes in the timeline -- you might want to take a look at the online help for more detailed information.