Updating Motion elements with a macro / VBA?

Hello all,

I have a population of assemblies, all with the same named action/reaction forces with expression defined functions. 

I have been trying to figure out a macro or VBA code that will allow me to change the properties of each of these forces.  That is, I want to open an ACTION/REACTION FORCE, populate its function expression with my pre-written FORTRAN string from an excel spreadsheet, then save and exit.  Right now, this is a super-tedious copy-paste nightmare.

Because each of these assemblies has ~150 forces, I would ideally iterate this to search, copy, replace for each force in the assembly/spreadsheet, with a WHILE or loop command.

I have seen some VBA calls for FORCEs in Motion, but I'm not sure how to input/replace my FORTRAN text string into the expression dialog from there.

http://help.solidworks.com/2011/English/api/swmotionstudyapi/SolidWorks.Interop.swmotionstudy~SolidWorks.Interop.swmotionstudy.IMotionStudy~CreateDefinition.html

Thanks so much to all you gurus,

meade

SolidworksMotion Studies