I currently using SparkyLinux Xfce x64. :)
Add siduction lxqt repository:
http://packages.siduction.org/lxqt/
I added the repository and installed the LXQt and did logout and login but I don't understand where is LXQt? How do I change to new LXQt?
The installation process as you described http://sparkylinux.org/forum/index.php?topic=2667 hasn't been finished due to missed packages so it has not been installed. That's why you can't launch it.
Never mind this bug, I just installed Sparkylinux JWM 32-bit. Thanks.