Random, but weird!

I set up a soft synth and verify that it works as expected and the patch sounds as expected using my midi controller (Axiom 61).  All is well.
 
I import a midi files exported from Guitar Pro on a client's mac and the synth then ceases to make noise/music.  If I delete the clip, the synth will not make music anymore.  I can manually paint notes throughout the grid, play on my Axiom, nothing works.
 
I've tried it with Dimension Pro, Session Drummer, and (I am sorry if I'm remembering incorrectly... it was late) Waves Element.
 
Anyone have any idea what the issue may be??

The MIDI files have extra data in them the sfz engine synths do not like. You can either clean up the MIDI files in the event viewer and/or BEFORE playing the files click on the VST2 header of the synth, open the Plug-in Properties and check the "Do not intercept NRPNs."

Wow thanks for the screen grab!!!
Just curious, what kind of events would I be looking for if I was to manually clean up??

Everything that is not a note or CC. Might even nuke the CC data depending on the synth and patch.