1) You would need a program to edit .exe files i.e. Resource Hacker: http://www.angusj.com/resourcehacker/
2) Find the image you want to change and export the image.
- Export image
3) Edit the image
4) Replace the image using the Resource Hacker program.
- Replace image
Open edited image
Choose edited image to replace original
Click on replace
5) Do that for all the images you want to edit
6) Save the file. Make sure to have a backup of the original .exe file.
Here are some of the pics of the exe file I edited.
Before pics:
After pics:
