msorrels
I don't have Maschine but how SONAR works with routing one VST that generates MIDI into another is pretty much the same always.  You will have to enable MIDI output in the Maschine VST.  For soft synths that usually means checking the box to enable MIDI output when you add the synth.  Or enabling MIDI output from the controls at the top of the VST window (in the VST2 drop down).  You may also have to enable Maschine itself to generate/output MIDI (something in it's options/preferences, Kontakt is like that). 
 
If you do both of those you should have a Maschine MIDI in the MIDI input list that you can use in the other soft synth's MIDI track.  Since you don't see Maschine in the MIDI input list, then you need to correctly configure it to generate MIDI output.

 
You rock , since i was using an old  maschine Template i cheked and the midi out wasn't cheked ....creating another Template as i type , thks guyz !!!!

I only just picked up Maschine a couple of weeks ago so I am very new to this.
I have found that if I set up a the midi track and then set the output to superior Drummer and then the input from Maschine (not in midi mode)
Also in the Group Batch midi setup option I change it from sounds channels to sounds to notes
Then change the bass note in pad mode of Maschine down from C3 to C1 I can then use Maschine to trigger Superior Drummer.
 
I then created and saved empty kit in maschine with the colours and names for the pads for easy recall.
There may be a better way but this does work and also allows me to try midi from/in Maschine and edit it as well.

Crowned One
I only just picked up Maschine a couple of weeks ago so I am very new to this.
I have found that if I set up a the midi track and then set the output to superior Drummer and then the input from Maschine (not in midi mode)
Also in the Group Batch midi setup option I change it from sounds channels to sounds to notes
Then change the bass note in pad mode of Maschine down from C3 to C1 I can then use Maschine to trigger Superior Drummer.
 
I then created and saved empty kit in maschine with the colours and names for the pads for easy recall.
There may be a better way but this does work and also allows me to try midi from/in Maschine and edit it as well.

The way to go .... usually you can open your drum thingy in Maschine , this is what i do but toontrack stuff don't get reconised ...
 
you can have a sound (in maschine) slot per sound , or one sound for all the kit using the Pad mode Keyboard , you will then just play with the octove up  or down and trigger the sound you wants in teh pads you want ...i found this better since there's so many sounds in toontrack , the per sound note is good if you trigger a vsti with 16 fixed type of sound ....
 
don't know if i'l clear lol