Second themepack always shows wrong pictures

[skidajmo]

I want to create two custom Windows 7 themes, Misc and Misc2. In C:\Users\Username\AppData\Local\Microsoft\Windows\Themes\ I've created two folders Misc and Misc2 both containing DesktopBackground folders. In each of those folders are different pictures.
I have put two .themepack files, one in Misc and another in Misc2.
I have changed Misc2 to appropriate name

DisplayName=Misc2

and changed

[Control Panel\Desktop]
Wallpaper=%USERPROFILE%\AppData\Local\Microsoft\Windows\Themes\Misc\DesktopBackground\first_picture_in_misc2_wallpapers_folder.jpg

No matter what I do Misc2 folder keeps on showing Misc pictures, even after I change it in Desktop Background options and save it after that.
I went through whole .themepack file with an advanced text editor, and there isn't option that possibly could tie that Misc2 pack to a Misc.
I'd appreciate some help.

 

[skidajmo]

I have changed

ImagesRootPIDL=content

in Misc2 to

ImagesRootPath=%USERPROFILE%\AppData\Local\Microsoft\Windows\Themes\Misc2\DesktopBackground\

And it seems that it works. If you have some other ways to do this please let me know.
One more thing. Modified Default sound theme isn't accepted.
I changed

[Sounds]
; IDS_SCHEME_DEFAULT
SchemeName=Windows Default

to

[Sounds]
; IDS_SCHEME_DEFAULT
SchemeName=Windows Default Modified

Is there any way to keep that modified theme saved so it can be later exported together with themepack?