Skin helper service : stripstring

I am trying to split ListItem.FileName for use on the movie information window (View_50_List).

Via this forum I found the stripstring service from marcelveldt, which should solve my problem.

Like marcelveldt stated in his skin helper thread (“If you want to have an example of how to implement all stuff in your skin, you can look at the Titan skin.”) I searched the Titan skin for an example.
I tried all kinds of approaches that I deducted from the (unrelated) RunScript examples I found, but I am stuck.

This is what I am trying to split, but I don’t know how and where I should put this statement.
RunScript(script.skin.helper.service,action=stripstring,splitchar=-,string=$INFO[ListItem.FileName],output=ShortCast,index=1)

I am not a skinner, just a web programmer ;-), so I hope someone can provide me with a working example or point me in the right direction.
Any help will be greatly appreciated!