Copying uv-channel 2 to uv-channel 1 within one object automized? Adressing the save .uvw-dialog?

Dear Users,

I have tried to write a script that copies uv-channel 2 to uv-channel 1 of selected objects, but always within one object. I want to do this automatically for hundreds of objects before I export them to a game engine. I want to do this because channel 2 contains the baked gi-texture, while the engine only supports channel 1. channel 1 in max contains my tiled floor-texture, for example.

Is there a way to address the dialog window in max that saves the uv-map as .uvw-file? I can use a maxscript that hits the button "Save" for the uv-map in the "Unwrap UVW"-modifier, but I don't know how to tell max to save the file under a specified location.

Could anyone help me with this? I can post the maxscript that I wrote so far.

Thank you!