I followed all the instructions, but it says that a certain file is broken and won't install. What should I do?

Does WoG install and run normally?
Try renaming the .wog file to .rar and opening it as a regular archive. If it opens, you can manually copy its contents, preserving the paths (i.e., what's in the archive in the \Data folder, copy it to the corresponding folder in Heroes, etc.). However, before copying, you need to delete all the contents of the \Data\s folder (or move it to another location); only T-script files should remain, otherwise, they will conflict with WoG's scripts.