Like the title suggests, I wonder whether there is a code which makes this possible.
I had tried assigning both cost reduction bonus modules to be given through different upgrades, but it does not work.

EDIT: Oops, I posted the thread in the wrong section, as my mind's a bit messed up due to exhaustion. Please move this thread to Generals/Zero Hour modding section.

Well codewise its not possible in shockwave mod, but it is possible in ROTR.

How this works- I have no idea but check the code.

Hell you can have something that makes everything MORE expensive, looking at you mr.Oil Sabotage GP from ROTR

It's possible, ShW just wasn't properly coded in this regard. IIRC what you need to do is make the Command Center grant the Cost Reduction upgrade (and for security such as cross-teching, every other structure players can build, as well).

I believe this is possible, in fact it'd even stack with ShW's vChina upgrade so the lowest you pay for a Battlemaster is around $300! I am fairly sure this still happens. (If you capture a Oil Refinery, Kwai's Industrial Plant and that Optimised Production vChina has)

The Battlemaster production is actually just a change of the build button, not the same function as the Cost Reduction from the Oil Refinery or Industrial Plant.

Can you post the detailed code here? I'll try it and see if it works.

Just this... I think.