1) Direct Method
(based on info found on the MS Resource center)
Copy paste the language files on the installation source directory. No overwrites occur(except 2-3 files which are essentially exactly the same). If i run setup normally(no switches etc) i get the message on the screenshot attached and continue the Installation normally and everything is good. However, when i create an *.MSP file to make the installation silent, i still get prompted to choose and until i click next the installation pauses. So i can't figure out a way to get rid of that message.

2) Indirect Method
Install Office 2007 normally with my already created installation which has been tested and works great, and then apply the language pack. However, there is no way to customize the installation the same way as office is, not even make it silent. I copied some files from the office 2007 to enable the /admin command but that does't work either.
3) Alternative Method
I tried to somehow add the proofing tools to the original installation, by copying the appropriate files and editing .xml but that didn't work either. Setup said there were no applications to install and didn't even start the process.
Any ideas? : )

