I can't get this to happen, but I sure had fun trying :D
Does it happen to anybody else?

When "locking" Windows XP (windows key + L) with the game window focused and returning, I received a "Win32 API function failed" error message and black screen. After doing it a second time, the game completely froze and I was unable to close it without using the task manager to force kill the process.

While on Classic in some sparring rooms that disable weapons, such as gc_sparring_01.nw - the weapons are not (re)enabled when they should be. The reproduce this, it's best to have a (Game Coordinator) tag in the said level and type "start" without quotes to enable the weapons ; "stop" disables the weapons. Using version 2 there is no problem, but it does exist in v3.
[Edit] Note, this uses save[]

I do not experience this problem with either Graal 3 or 4. :o

I have no problem with Graal v3 doing this, but it's a different case with Graal v4. For me it's reproducible on multiple XP (SP1/SP2) machines, and doesn't appear to happen on Windows 2000/2003. One of the machines uses an ATI video card while the other uses NVIDIA; Both are using DirectX 9.0c with the newest drivers etc.
I have my XP user accounts passworded (hence the "locking"), if that matters. I'll see what else might affect it and edit my post later when I have more time..

[Edit]
Ohh, seems to only happen when the playerlist is open, even if one or both of the windows are minimized. Big key there >_<

[Edit2]
Seems that we can't play music etc. with another program while Graal v4 is running- I think if that's true, quite a few people won't appreciate it.

I have no problem with doing this myself. Get a better sound card?

Although it's not the best, I have a SoundBlaster Audigy 2 ZS card -- I can normally play other games (including Graal v2 and some 3D games with a lot more happening) while listening to music at the same time without having a problem. It actually works on my laptop which has some of the worst built-in audio there is right now. So I don't believe it's really a question of the performance/quality of the card, but the options that the game's using for (DirectX?) sound output etc. that might make it do this on certain cards; Maybe more of a compatibility problem? It just seems like Graal is 'stealing' the audio output from anything else while it's in use -- e.g. the music will 'play', but it appears to be 'muted' at the time.

Graal v3 and v4 use the same sound library like WoW. I am setting the option for continuing the music even if the program doesn't have the focus though, may be that is the problem ?

I don't think that's what I meant. The Graal music plays fine for me, but I normally have it off anyway. What I tried to do is play some external music (MP3s) with some other program like Winamp, while Graal is running. I can do this fine with Graal v2, but not with v4 when I use the Audigy 2 series sound cards (although it may happen with others too)..
It's not really a bug, but it will probably bother some people if they happen to have a sound card that experiences this.

It works fine for me. o_O

Do you have the volume meter down on graal? That usually causes the problem, I had the same problem with midis.

I do not think you read the post correctly.
Is Winamp the only other program you have tried?

The playerlist icons should be more clear, e.g:
*CONNECTED SERVER = 1 Noob head
*ALL SERVERS = Multiple noob heads (Currently the connected server icon)

And the icons should stay the same, not change to PM bubbles when you get a PM so its easy to navigate still, else it gets confusing as to what each tab is for.

If possible a better icon for guilds? I don't know, would be hard to think one up.

With v2 those things don't happen?

The new icons for the player list tabs have been added because the text is too huge if you have 5 tabs ;) I tried to find good gfx, if someone wants to make nicer ones then he/she is welcome to do so. The server icon is displaying part of the earth ball, like on the RC.

Ajira and Stormie tested it, it doesn't :(

The problem with the variables in cheetos_variables.nw is that the clientside script of local npcs is still handled as old script, need to fix that.

Update: fixed it