Eclipse RCP Application Branding

I have an RCP application that I want to "tag" ie. create correct text for about field with assembly id. Simple things. Unfortunately it wasn't as easy as I hoped and now I am stuck.

My RCP project is started from project config and is not deployed as plugins via functions.

I tried to inject stuff directly under Product Config -> branding, but when I do, the input is not formatted, which means I have no newlines and no way to preempt lines like I want. I also tried creating about.ini, about.properties and about.mappings in an attempt to use% <property>, but still no luck. The about window is the standard org.eclipse.ui.help.aboutAction.

Every tutorial on the net says different things, so now I feel pretty confused. I have also tried to replicate what is being done with branding in the Eclipse repositories, with no luck.

Does anyone know what I am doing wrong?