There are only a few things I can think of that would cause it to not work.
1. Your trying to use the mod on the android version which this mod does not support.
2. You installed the mod wrong.
Since I doubt your trying to use this on android let me explain how to install the mod.
1. Extract the contents of the zip.
2. There should find two folders. One called data and the other called img.
3. In the Zombie Retreat 2 game folder you should see a folder called www open that folder.
4. Copy the two mod folders and paste them in the www folder. You should get a message about files with the same name. Replace all the files.
5. That's it the mod should be installed.
After the day 1 you should see a crystal and a sparkle downstairs. The crystal will take you to the gallery room and the sparkle will tell you what salvage bonus each character has.
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Remember the day counter needs to be at least 2 for the mod take effect. If you are not sure about your day count check the save screen.
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