Apple Logic Pro /LogicExpress Discussion

I am working on a full orchestra file - piccolo down to basses- which i created with midi files 
generated from finale.
My problem is that after i assign names and instruments patches to the tracks, the oboe 
name and assigned instrument "takes over" those belonging to the rest of the woodwinds, 
thus the piccolo, flutes and clarinets are "turned" into oboes.
What, if all, am i doing wrong?

Thank you

GR

Here is what i am working on and with.
Mac G5 with 5 GB memory
Garritan, Kirk Hunter, Symphonic Choirs,etc.
Logic Pro 7