I asked the same question once, and was pointed to aptrigga (now there's aptrigga2). This little guy will do EVERYTHING you want, and it's only $39. I don't work for this guy, but I'll sing its praises all day - it's saved my butt several times.

http://www.apulsoft.ch/aptrigga/

There´s a way using the the exs24:

1. Create a clean audioinstrument-track for the exs24 that contains the sample to be trigged
2. While leaving the empty exs24-track selected, double-click the audiofile with the original recorded kick
3. Now you´re in the sample editor window. Under the menu "factory" you´ll find a function called "audio to MIDI groove template". Select that.
4. Now you´ll find a bunch of parameters to play with. Adjusting the threshold you´ll find a good level where you get the kick but not the leakage. Under the waveform it also displays the "result". Set Quantize to "3820none", otherwise you´ll get 1/16-notes...
5. When you have the parameters set to fit the track, click "use" and exit the sample editor
6. Now there is a (muted) object on the exs24-track containing midi-notes. These should be the same as the original kick when it comes to timing and velocity. For some strange reason sometimes Logic spreads the notes out so you might have to set all notes manually to the note where the sample is (ie. C1).
7. Unmute the track and play. Your kick is now trigged.

THANK YOU!!! that helped me more than you will ever know!!!

you da man!! 8-)