Theme container:
Code:
<?xml version="1.0" encoding="UTF-8"?>
<theme>
*REST OF THE DATA*
</theme>
Information:
Code:
<infotable>
  <info
    name=""
    icon=""
    url=""
    author=""
    authoricon=""
    genre=""
    version=""
    comment=""
    preview=""
  />
      <localizedinfo
      locale="en"
      name=""
    />
</infotable>
Definitions:

name = Themes name
icon = Themes icon (64x64 jpg)
url = Your url
author = Your name
authoricon = Your icon (54x54 jpg)
genre = Genre
version = Version number
comment = Theme comment
preview = Preview image (480x270 png)
locale = locale (en, jp, kr, etc)

To make language specific names/comments/etc do as follows:
Code:
<localizedinfo
      locale="en"
      name="english name"
    />
      <localizedinfo
      locale="jp"
      name="japanese name"
    />
      <localizedinfo
      locale="fr"
      name="french name"
    />
Available languages: en, nl, de, fr, no , sv, zh_s, ko, pt, it, es, jp, da, fi, zh_t, ru

Background:
Code:
<bgimagetable>
  <bgimage hd="hd_1.jpg" sd="sd_1.jpg"/>
</bgimagetable>
Definitions:

hd : HD background image (jpeg format) 1920x1080
sd : SD background image (jpeg format) 640x480

To use multiple background images (selected randomly or manually from the theme), simply include more than one definition of bgimage like so:
Code:
<bgimagetable>
  <bgimage hd="hd_1.jpg" sd="sd_1.jpg"/>
  <bgimage hd="hd_2.jpg" sd="sd_2.jpg"/>
  <bgimage hd="hd_3.jpg" sd="sd_3.jpg"/>
</bgimagetable>
Cursor (browser):
Code:
<pointertable>
  <pointer id="pointer_arrow" src="" base_x="20" base_y="2" />
  <pointer id="pointer_finger" src="" base_x="16" base_y="10" />
  <pointer id="pointer_click" src="" base_x="16" base_y="10" />
  <pointer id="pointer_pen" src="" base_x="6" base_y="38" />
  <pointer id="pointer_hand" src="" base_x="23" base_y="17" />
  <pointer id="pointer_grab" src="" base_x="23" base_y="17" />
</pointertable>
Definitions:

pointer_arrow: Default cursor
pointer_finger: Cursor "hover" for things like radio/check boxes
pointer_click: 'click' image for cursor, what you see when you press/hold down the button
pointer_pen: Cursor "hover" image for text input boxes
pointer_hand: Cursor for moving objects in the page, or moving the page around (scrolling)
pointer_grab: Same as pointer_hand, but image shown when holding down the button.
base_x="" X axis location relative to 0,0
base_y="" Y axis location relative to 0,0

Sound:
Code:
<setable>
  <se id="se_decide" left="decide_2.vag" right="decide_1.vag"/>
  <se id="se_cursor" left="cursor_2.vag" right="cursor_1.vag"/>
  <se id="se_optionmenu" left="optmenu_2.vag" right="optmenu_1.vag"/>
  <se id="se_cancel" left="cancel_2.vag" right="cancel_1.vag"/>
  <se id="se_system_ok" left="ok_2.vag" right="ok_1.vag"/>
</setable>
Definitions:

se_decide: the 'beep' when a popup opens to ask you something.
se_cursor: the click of icons when scrolling left or right.
se_optionmenu: the sound made when opening options, such as pressing triangle on files.
se_cancel: sound made when cancelling
se_system_ok: sound made when accepting
left: left speaker sound
right: right speaker sound

.WAV to .VAG and vice versa : http://www.fmjsoft.com/awframe.html

Icons:
Code:
<icontable>
  <icon id="icon_user" src="" />
  <icon id="icon_setting" src="" />
  <icon id="icon_photo" src="" />
  <icon id="icon_music" src="" />
  <icon id="icon_video" src="" />
  <icon id="icon_game" src="" />
  <icon id="icon_network" src="" />
  <icon id="icon_friend" src="" />
  <icon id="icon_tv" src="" />
  <icon id="icon_newuser" src="" />
  <icon id="icon_update" src="" />
  <icon id="icon_game_setting" src="" />
  <icon id="icon_bdvd_setting" src="" />
  <icon id="icon_music_setting" src="" />
  <icon id="icon_chat_setting" src="" />
  <icon id="icon_system_setting" src="" />
  <icon id="icon_theme_setting" src="" />
  <icon id="icon_datetime_setting" src="" />
  <icon id="icon_accessory" src="" />
  <icon id="icon_printer_setting" src="" />
  <icon id="icon_display_setting" src="" />
  <icon id="icon_sound_setting" src="" />
  <icon id="icon_security_setting" src="" />
  <icon id="icon_remoteplay_setting" src="" />
  <icon id="icon_network_setting" src="" />
  <icon id="icon_setting_item" src="" />
  <icon id="icon_photo_default" src="" />
  <icon id="icon_photo_album_default" src="" />
  <icon id="icon_music_default" src="" />
  <icon id="icon_music_album_default" src="" />
  <icon id="icon_video_default" src="" />
  <icon id="icon_video_album_default" src="" />
  <icon id="icon_mediaserver_search" src="" />
  <icon id="icon_ms" src="" />
  <icon id="icon_sd" src="" />
  <icon id="icon_cf" src="" />
  <icon id="icon_usb" src="" />
  <icon id="icon_pspms" src="" />
  <icon id="icon_usbcamera" src="" />
  <icon id="icon_usbaad" src="" />
  <icon id="icon_gamedata" src="" />
  <icon id="icon_savedata" src="" />
  <icon id="icon_vmc" src="" />
  <icon id="icon_newvmc" src="" />
  <icon id="icon_onlinemanual" src="" />
  <icon id="icon_remoteplay" src="" />
  <icon id="icon_browser" src="" />
  <icon id="icon_download" src="" />
  <icon id="icon_accountmanage" src="" />
  <icon id="icon_blocklist" src="" />
  <icon id="icon_addfriend" src="" />
  <icon id="icon_playermet" src="" />
  <icon id="icon_chat" src="" />
  <icon id="icon_chatroom" src="" />
  <icon id="icon_mbox" src="" />
  <icon id="icon_mbox_received" src="" />
  <icon id="icon_mbox_sent" src="" />
  <icon id="icon_mbox_create" src="" />
  <icon id="icon_default_h" src="" />
  <icon id="icon_default_v" src="" />
</icontable>
Definitions:

These are all really obvious icon names, you should know them all, icon format is PNG, size 128x128 except for the ones stated in red below.

Horizontal icon set:

icon_user
icon_setting
icon_photo
icon_music
icon_video
icon_game
icon_network
icon_friend
icon_tv

User icon set:

icon_newuser

Setting icon set:

icon_update
icon_game_setting
icon_bdvd_setting
icon_music_setting
icon_chat_setting
icon_system_setting
icon_theme_setting
icon_datetime_setting
icon_accessory
icon_printer_setting
icon_display_setting
icon_sound_setting
icon_security_setting
icon_remoteplay_setting
icon_network_setting

Setting submenu icon set:

icon_setting_item

Photo, Music and Video icon set:

icon_photo_default - 170x128
icon_photo_album_default - 170x128
icon_music_default
icon_music_album_default
icon_video_default - 228x128
icon_video_album_default - 228x128
icon_mediaserver_search
icon_ms
icon_sd
icon_cf
icon_usb
icon_pspms
icon_usbcamera
icon_usbaad

Game icon set:

icon_gamedata
icon_savedata
icon_vmc
icon_newvmc

Network:

icon_onlinemanual
icon_remoteplay
icon_browser
icon_download

Playstation network icon set:

icon_accountmanage

Friend icon set:

icon_blocklist
icon_addfriend
icon_playermet
icon_chat
icon_chatroom
icon_mbox
icon_mbox_received
icon_mbox_sent
icon_mbox_create
icon_default_h
icon_default_v

Misc graphical:
Code:
<notification src="notification.png" />
This image is small, only 64x64, but the outer edges, are stretched across to fit, try not to use a pattern on this, keep it basic or it will look distorted.
Code:
<font selection="" />
<color selection="" />
Setting these elements overrides defaults set on the system.

Font selections are as follows:

0 = Original
1 = Rounded
2 = Pop

Color selection is the tint to the text and side menus, the colors are as follows:

0 = Original (Uses system timer set color)
1 = White
2 = Yellow
3 = Light green
4 = Pink
5 = Dark green
6 = Pale purple
7 = Cyan
8 = Dark blue
9 = Purple
10 = Orange
11 = Brown
12 = Red