Some questions regarding the AppImage split from another topic

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Hi!!
Very nice! I just downloaded it to my linux mint 18. Before I used to have the old 1.1.3 version which is much more different.
This one ( I mean, the RC8 now) has some things that I was missing from the old one, but there are two things that I havent found out yet:
-How to change to the old "brighter" theme, or it doesnt have to be the old one, but not dark as it is now by default. (I know you mention the possibility of changing that in settings, but there is no option for that, I have search it and nothing).
-I downloaded the appimage, which is the way to install it I guess. That has been really easy to do, the problem is, now I don't see the program between my other programs, and if I type lmms in terminal, it says "The program 'lmms' is currently not installed. You can install it by typing: sudo apt install lmms"
So, how do I make it to have this version but installed and recognized by my computer as a program?? maybe because I didnt reinstall as an administrator.. but how do I do that?

thanks
@growing Hi! I split your post from the original announcement to the support section where it'll be more easily found.
growing wrote: -How to change to the old "brighter" theme, or it doesnt have to be the old one, but not dark as it is now by default. (I know you mention the possibility of changing that in settings, but there is no option for that, I have search it and nothing).
Menu -> Edit -> Settings -> Paths
Scroll down to THEMES DIRECTORY which probably reads something like data:/themes/default/
Click the directory icon by the side and navigate up in the gui where you'll be presented with the themes default and classic.
Choose classic. Press OK and restart LMMS.

growing wrote: -I downloaded the appimage, which is the way to install it I guess. That has been really easy to do, the problem is, now I don't see the program between my other programs, and if I type lmms in terminal, it says "The program 'lmms' is currently not installed. You can install it by typing: sudo apt install lmms"
So, how do I make it to have this version but installed and recognized by my computer as a program?? maybe because I didnt reinstall as an administrator.. but how do I do that?
You need to install the appimaged daemon. It will find the AppImages and register them with your OS.
https://github.com/AppImage/appimaged