I created an eventtype and at creation it lets you choose a style color. It works fine for me as admin when i run a search. The desired events are red as expected. I made the eventtype shared to all apps and set permissions to Global, Everyone can Read.
When another user logs in, they are unable to see the color coding i set. I don't see any way to edit the style except at creation of the eventtype and can't figure out why the other users cannot see the color style.
eventtypes.conf is where the eventtype color is set. Make sure the eventtypes.conf where your configuration is made is one that is available to other users.
[sourcetype]
color = et_green
It sounds like yours may be in etc/users instead of etc/app.