There's actually a pretty simple way to run the game without a disc. Again, everything here comes down to the file MATH6-9.ini. You'll notice when opening the file that the executable reads from "<drive>:/Data.

Opening the disc to view the files, you can see the folder called DATA. You can just copy this folder to another location. I copied mine directly into the main game's folder.

Once that's done, copy the address of the folder. Open MATH6-9.ini and go to the second line down, which reads the address the executable is attempting to read from. Replace the current address with the address you copied. Make sure the address ends with \Data\ as otherwise it's not reading the correct folder.

The game should now run fine without needing to have the disc in the drive.