Wow, thanks for all the replies, especially for the download and the youtube link!
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Unfortunately I have not made much progress...
So, I have set up the path as in the youtube vid correctly to 1.3_20/bin (thanks Kazegami!)
When I double click on the Resolve batch file (thanks Verhangis!) the CMD window flickers up for a split second and then dissappears.
When I bring up CMD manually and type java -jar classresolver.jar ./Resolve into it it now says "classresolver v 0.2 written by tim" etc. instead of the error I had before, so that's progress.
But I can't find the resolved files! I expected them to appear in the Resolve folder, but they do not.
Verhangis, you said the files would be resolved to a new folder called 'com' but I can find no such folder. The com folder in DBW just holds the usual text files.
I am trying to use the Resolver to open files like B27261D242F3990A so I can find out how they work and make my own. Is this the correct usage?
Sorry for being such a newb, but we all have to start somewhere, right?!
Thanks for turning me into a Modder by the way, whoever did that. I wear my new badge with pride!
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Hope I can do it justice...