Well, the error is clear. The problem to write a jnlp is that the game depends on files like options.properties and files in resources/. I think i have to modify the code to include and access resources inside the jar. I could also generate a default options.properties if not found.

Well, i'm very busy right now so if you want to help me with jnlp i'd appreciate it very much.

You have to start the game with HokutoNoRogue.bat, or HokutoNoRogue.exe. Do not double click HokutoNoRogue.jar. Or from command line try this:

javaw -jar -Xmx256M -Dsun.java2d.opengl=true HokutoNoRogue.jar

Thank you gouessej. 
Gtge is now open source: http://code.google.com/p/gtge/
In the next major release I'll include a JNLP file.
Btw, I've fixed a bug on GO UP/GO DOWN action so I've released the 0.4.1 version.

Hi everybody.
My name is Alessio and I'm from Italy.
I'm working on a graphical roguelike called Hokuto no Rogue. The game if set in the world of Hokuto no Ken (aka Fist of the North Star, Ken il Guerriero, Ken le Survivant). It's written in pure Java and features special moves, music, graphics effects and allies.
I've used Golden T Game Engine
It's my first game so don't take it as an example of good game programming.
The game is not complete but it's already playable. It requires Java 6.

Download ver 0.4.1 prealpha

Game Trailer

Screenshot:


Enjoy!
Bye.