Because they don't work in XP. Once you have another user sharing the same machine on mirc-pre-6.3 you'll find that you'll be forced to share the settings for every user account on the system.

Well seen as im the sole and only user of my PC and nobody in my house has access to the machine, why should i setup multiple accounts ?

Making something "work like XP" is only considered "fixing" it if it worked better on that OS than Vista. In your case it may not work any better (that doesn't mean it's any worse), but for many, the AppData changes improved the program

No it doesnt work any better using that AppData folder, esp when my mIRC bot USED to work.

Finally, if you upgrade a pre-Vista version of mIRC (before AppData compatibility), you'll find that the new mIRC will work the same way it did before

I always try to get the latest version of any software i install, except Windows Vista, if only you knew how much i hate that OS, my Brother, Father and Girlfriend all have laptops with Vista installed, and they come to me, Vista wont load this, Vista wont load that.

in fact, most users nowadays should expect application data to live in AppData (or Documents), not in the Program Files directory

Ok i see the point of SOME things needing to stay in the AppData
folder and NOT in the Program Files directory, i dont know what else to say on this one.

But hey come on give it a shot, tell me how i can have my Main mIRC and my BOT, in two different folders using the folders

C:\Program Files\ShadowDemon
C:\Program Files\bot

WITHOUT USING and SHARING my AppData folder, or have one folder for the ShadowDemon and one for the bot,
Because RusselB (sorry to have you on this thread i replied to argv0, that solution you gave me with the //echo -a $mircdir
has suddenly stopped working, i fire up ShadowDemon, all is well, and the fire up my bot and i get the please change your bots nick, as ShadowDemon is in use on this server

Never argue with an idiot...they'll drag you down to their level and beat you up with experience