It is possible to customize the shortcuts which are displayed on bottom of the remote. This is not possible from within the application. You have to create your own configuration file on your PC and then copy it to the right place on your device

Note: The shortcut section is only present in the unlocked version

Create custom config file

The syntax of the config file is not complicated.

[
  {
    "command": "ActivateWindow(PVROSDGuide)",
    "name": "Guide"
  },
  {
    "command": "ActivateWindow(TVChannels)",
    "name": "TV"
  }
 ]
name: Name of the shortcut button
command: Command which should be executed when clicking the button.
You can use built-in functions / actions from Kodi

Additional information about actions and functions

A list of available functions is documented in the Kodi Wiki at http://kodi.wiki/view/List_of_built-in_functions
A list of available Action IDs is documented in the Kodi Wiki at http://kodi.wiki/view/Action_IDs
You can also look at existing Kodi keymap files to find actions/functions https://github.com/xbmc/xbmc/tree/master/system/keymaps.

There is a tool called kodi-send bundled with kodi (at least on the linux version) which you can use to try out the commands.
For instance to test the function to activate the screensaver you can execute the following command:

kodi-send --host=192.168.1.110 --action="ActivateScreensaver"
And then add it to your custom config file using
{
  "command": "ActivateScreensaver",
  "name": "Screensaver"
},

Remark: The file has to be a valid json file otherwise it won't load in the application. Don't forget to add the required , and " as shown in the examples (There is no "," after the last command). In doubt you can validate the file using an online json validator (e.g. http://jsonlint.com/ )

Copy config to your device

Once you have created your configuration file save it under the name custom_remote_buttons.json and then copy it to your android device into following folder /mnt/sdcard/Android/data/ch.berard.xbmcremotebeta/custom_remote_buttons.json

Remark: The new configuration gets activated once you restart Music Pump Kodi Remote.

Example - PVR Shortcuts

Replace the shortcut section with a list of buttons that are useful for PVR

Config file (Download)

[
  {
    "command": "ActivateWindow(PVROSDGuide)",
    "name": "Guide"
  },
  {
    "command": "ActivateWindow(TVChannels)",
    "name": "TV"
  },
  {
    "command": "ActivateWindow(PVROSDChannels)",
    "name": "Channels"
  },
  {
    "command": "Number1",
    "name": "1"
  },
  {
    "command": "Number2",
    "name": "2"
  },
  {
    "command": "Number3",
    "name": "3"
  },
  {
    "command": "Number4",
    "name": "4"
  },
  {
    "command": "Number5",
    "name": "5"
  },
  {
    "command": "Number6",
    "name": "6"
  },
  {
    "command": "Number7",
    "name": "7"
  },
  {
    "command": "Number8",
    "name": "8"
  },
  {
    "command": "Number9",
    "name": "9"
  },
  {
    "command": "ActivateWindow(Teletext)",
    "name": "Teletext"
  },
  {
    "command": "Number0",
    "name": "0"
  },
  {
    "command": "AudioNextLanguage",
    "name": "Language"
  },
  {
    "command": "Action(ToggleFullscreen)",
    "name": "Toggle Full Screen"
  },
  {
    "command": "ActivateWindow(filemanager)",
    "name": "File Manager"
  },
  {
    "command": "AspectRatio",
    "name": "Aspect Ratio"
  }
]

Example - Default Shortcuts

This config file contains the default shortcut so you don't have to create a new config from scratch.

Config file (Download)

[
  {
    "command": "ActivateWindow(PVROSDGuide)",
    "name": "Guide"
  },
  {
    "command": "ActivateWindow(TVChannels)",
    "name": "TV"
  },
  {
    "command": "ActivateWindow(PVROSDChannels)",
    "name": "Channels"
  },
  {
    "command": "Number1",
    "name": "1"
  },
  {
    "command": "Number2",
    "name": "2"
  },
  {
    "command": "Number3",
    "name": "3"
  },
  {
    "command": "Number4",
    "name": "4"
  },
  {
    "command": "Number5",
    "name": "5"
  },
  {
    "command": "Number6",
    "name": "6"
  },
  {
    "command": "Number7",
    "name": "7"
  },
  {
    "command": "Number8",
    "name": "8"
  },
  {
    "command": "Number9",
    "name": "9"
  },
  {
    "command": "ActivateWindow(Teletext)",
    "name": "Teletext"
  },
  {
    "command": "Number0",
    "name": "0"
  },
  {
    "command": "AudioNextLanguage",
    "name": "Language"
  },
  {
    "command": "Action(ToggleFullscreen)",
    "name": "Toggle Full Screen"
  },
  {
    "command": "ActivateWindow(filemanager)",
    "name": "File Manager"
  },
  {
    "command": "AspectRatio",
    "name": "Aspect Ratio"
  }
]