Do not attempt to install without preparing these 4 things first. Failure to do so will result in garbled text (mojibake), crashes, or the game refusing to launch.
Most English patches are manual installs: koumijima shuu 7 de umeru mesutachi install
Many copies of Koumijima Shuu 7 de Umeru Mesutachi require a separate crack or no-DVD patch. Check the original download source for a folder named Crack, Patch, or 起動用. Copy any .exe or .dll files from that patch folder into the game's installation directory, overwriting when prompted. Do not attempt to install without preparing these