"As a general rule of thumb, we don't mind if you do things like this to make your own playing experience more fun. Some people really like to mod, and we recognize that this can often be a valuable learning tool. When you're doing it, though, keep in mind that we ask that you don't use our content to mod other games. Please do not attempt to extract anything from your GW.dat with the intent to use it in a mod for another game or project. Also keep in mind that we can't support any changes you make.
In other words, if you try to make some changes and your game crashes, don't contact support because there really isn't anything they will be able to do for you. Make sure you have your disks handy to reinstall
In case anyone was concerned about this reply, keep in mind that alterations that people make to their own .dat files will not affect the play experience of others. All of that important data is stored server side, so any changes that would be able to be made are purely cosmetic. For instance, if someone re-textures their sword to look like a gigantic pickle, they will be the only one to see this change. You won't start seeing people wielding pickle swords running around in random arena any time soon
Also keep in mind that we are always interested to see what stuff you guys come up with. If you do something exceptionally cool that you feel would really benefit the community as a whole, don't be afraid to let us know about it." --Emily Diehl
"To all modders: It's important to note that the parameters concerning the use of third-party programs do still apply. We cannot condone the use of such programs, and we cannot support the accounts of those who may be negatively impacted in using such programs. That's called the If it eats your hard drive and blows up your refrigerator, don't call us policy.
Honestly, though, as previously stated, it is unlikely that we would actively pursue or action those who use such programs in a positive manner, that is, those whose only interest is creating benign mods of our games. Keep in mind that occasionally people get creative and might bring up the use of a harmless program to attempt to mask other harmful activities. We see that with other situations, such as where they say "But I was only using an alternative OS, why was I blocked?" and we discover they are using major bot programs.
If you feel that this creates a "mixed message," then I guess we should discuss that concern. I can understand where the strict "Don't do that" is clearer than "We can't say you can do that, but we won't take action if you do choose to do it." There are some cases where it's not black and white. One example that comes to mind is the use of emulators to play Guild Wars. We develop only for the PC, but others play on other systems and that's totally ok. However, if they develop difficulties, our Support Team is not available to help them resolve those issues. So we don't prohibit the alternative, we simply decline to support it.
What I want to say above all about this matter is that if you're going to mod, have fun, but do stick with the benign and positive uses of the programs and create mods that impact the game only in ways that are fun and harmless. If there's more information to share, I will do so as soon as it becomes available to me." -- Gaile Gray