Welcome to the forums, LightWalker
The 'credits' you've got there are actually a thing called a resource. Basically it's just a picture that is superimposed over the screen using the
cutrsc command.
What this means, is you can't change the text directly. However, you can create your own resources...
To do this you need to muck around with a file called
description.ext...
Unfortunately I'm not too good with resources myself, hopefully someone more knowledgeable than me will come along and help you out