manylith, i really have no idea what you are doing all day. You´ve been asking things about the essential routines of scripting for a half year or more now. If you would just sit down a day or two and look how those things really work you could easily solve those stuff on your own. You seem to fiddle arround in Tribes a lot so i don´t think you can´t spent the little time to learn some basics.
It´s no miracle. Data flows through functions, become redirected (e.g events) and end up in huds so you can see them. Especially when you have a working script like this viking script you should inspect it, find out that it mainly relies on killtrack and compare it to presto and see how you can make it compartible to it aka rewrite it.
Start by modifying a script that has works similar to what you want and already works on Presto, i´m sure there´s a script that does display something when somebody is killed. Approaching from that pov your filter hud is almost done.
My personal suggestion would be to make anything else to work with Viking/andrew/etc. pp. instead of doing a step backwards to presto and doing it vice versa.