Item description:

Tinker is a 3DS Homebrew Theme Manager for Shufflehax/Menuhax/Themehax. It is heavily inspired by CHMM2 and made using Rinnegatamante's lpp-3ds.

Note from developer:

For user with SysNAND+EmuNAND (CtrBootManager+Menuhax), please note that Tinker will only apply themes to SysNAND. To apply themes to EmuNAND you can safely use CHMM2 after launching HBL from within EmuNAND (via .cia or some other method).​

Installation
Extract archive and copy the Tinker folder to the 3ds folder on your SD Card.

Place your themes in a Themes folder at the root of your SD Card, just like you would for CHMM2.

Themes should each have their own folder with their contents in them like so:

Root
|-3ds/
| |-Tinker/
| | |-Tinker.3dxs (*)
| | |-Tinker.smdh
| | |-...etc
|-Themes/
| |-Theme1/
| |-Theme2/
| |-Theme3/

Theme1, Theme2, etc are just examples of theme names, your theme folders can be named anything, as long as they are in the /Themes/ folder.

Note: If you have a Japanese 3DS console, there is a bug in the (*) 3dsx file which stops Tinker from running. You'll need to download 15avaughn's patched Tinker.3dsx file and replace /3ds/Tinker/Tinker.3dsx with that patched Tinker.3dsx. Furthermore, launching 3dsx files doesn't work either, meaning after you press A to install a theme from the popup, you need to manually exit out of Tinker, enter Menuhax Manager and select Install Theme. These problems are only present on Japanese 3DS's.

User guide
How to use
Avilable themes are shown on the botton screen.

Theme preview will appear on the top screen. It will last about 5 seconds, then the bottom screen portion will appear. That will disappear after about 5 seconds and you should be able to move again.

Every time you change theme, it brings up a confirmation dialogue:

Pressing A will open up Menuhax Manager, choose Install Custom Theme to install the theme.
Pressing B will close the dialogue box and the theme will not be applied.
Once you applied new theme, you can exit the application and return to the Homebrew Launcher by pressing Start. This glitches out if you're using the Gridlauncher so you'll have to hold R+L+Down+B to exit.

Note: This only works for Menuhax theme implementation, use CHMM2 if you're looking for standard custom theme installation.

Create a theme
A theme is composed by several files:

body_LZ.bin - Contains background images and some theme settings.
BGM.bcstm - Contains theme BGM sound.
Preview.png/.jpg/.bmp - Preview screenshot/image.
BGM.ogg - Contains theme BGM preview sound.
info.smdh - Contains icon, author, description and title of the theme.
Recommended tools:

For the theme, you can use Usagi (theme editor), YATA+ (no .smdh) and SMDH Creator (.smdh only).
For the audio, you can use Audacity (music editor) and Looping Audio Converter (converter to .bcstm).
Controls
D-Pad - Browse available themes

Y - Theme preview

A - Apply theme, Install theme

B - Cancel

Start - Exit application and return to Homebrew Launcher (glitches if you use Gridlauncher, use R+L+Down+B instead)