Village_Monk has developed a mod to change the color of the mushrooms. You will need to change the name of the file after you download it to collectables_images.png before you place it into the images folder, or it won't work. Be sure to make a backup of the original file first, so that you'll have it if you want to go back to the original mushrooms.

Here is Village_Monk's description and the png file he edited:

I've included my graphic which i changed the hue of the brown mushrooms to purple and the hue of the red mushrooms to green. They are a LOT easier to see on most backgrounds than the originals

*** i am not responsible for anyone who messes up their games trying to implement a mod i created! ***

Download the mod from here.

Copy the graphic into your game images folder (c:\Program Files\Virtual Villagers - The Lost Children\Images) and then restart your game to see the effect.

Enjoy