645 PRO ayecon "icon"
I have 2 sets (versions) of the custom icon. Only two of the files are needed at a time and must be called:
I use i-Funbox for updating theme files. Go to Library/themes/ayecon Springboard.theme/bundles and create a folder called:
Move the icons for 645 PRO to that folder - respring - done!
Note: If you use iFile or SSH the folder path could look a little different (/var/stash/themes/ayecon Springboard.theme/bundles) I believe.
Unless the theme is updated with an official icon this will stay as part of the theme even if there are updates.