Sweet! It appears I have it working.
I'm currently getting the cross product of the force and the point of application, (relative to the COM) dividing the result by the mass and then multiplying the result by the elapsed time. I am then able to use the resulting vector to calculate the change...
Surely some force is transferred into angular rotation? If there was no rotation as a result of the force being in line with the COM, I would understand this.
When I have some more time I will get back to you. As it stands, I need sleep desperately, which is a great combination when it comes...
I'll preface this by saying I've done these sorts of problems before (though it was only in 2d) in my statics and dynamics class. I have no idea where my book went and the major problem I'm dealing with is vocabulary, so if I say something that doesn't make sense, please let me know, I've almost...