This method should work with any version of TQ AE for any marketplace (GOG, Steam, etc.) as it patches a separate part of the library.

1. Unpack this archive into a separate directory
2. Create a backup copy of "Game.dll" from the root directory of the game (just in case)
3. Place "Game.dll" in this directory
4. Run "XVI32_MerchantSizeFix.cmd" (recommended as Administrator) and wait until the patch complete
5. Put the patched "Game.dll" back into the root directory of the game
6. Play!