The PAM Theme Builder Portable is a full-fledged application in portableapps format.
While it is in the beta stage, it is fully functional, and hopefully will be added to the official apps in the future.
PAM Theme Builder Portable

ThemeBuilder is a tool to help you create Themes for 2.0b5, by displaying the theme as you edit the png files that make up the theme.
When finished, you can package it as a .patheme file, ready for installation in PAM 2.0b5.

You can Download ThemeBuilder Here.

Introduction

The PAM Theme Builder is an application to simplify the creation of custom themes for the PortableApps.com Platform Menu, from simple color changes to total conversions. When installed to the Platform, it works with your existing portable image editing applications to modify the theme images. It also includes an embedded editor for the PATheme.ini file, with color pickers to select font and background colors.

All the images are arranged to display exactly as they will appear in the Menu. As you edit the images and save them, you can refresh the display to see what your theme will look like. As you choose the colors in the INI editor, the colors in the display change and the ini file automatically updated.

At any time, you can package your work to a *.patheme file, the standard extension for a PAM Theme. You can unpack any theme that''s in the *.patheme format, even ones created by others.

One of the more difficult parts of theme building is dealing with the folder icons. These tiny pictures (24 x 24) are challenging to make, so many theme makers tend to reuse the same icons on different themes. PAM Theme Builder lets you save just these icons to an IconPack for use in other themes. IconPacks use the standard *.zip format.

The PAM Theme Builder is designed to optimize the process of theme creation, so you can more time on theactual design of the theme. I hope you find this useful, and look forward to seeing many great new themes!

Getting Started

The PAM Theme Builder first opens to show a default custom theme.
Choose Edit>Preferences to select a portable image editor that will auto-open the different image components when you select them from the Edit menu. Three official PortableApps.com image editors are pre-configured: GIMP, Inkscape, and OpenOffice Draw.
You can also choose any other image editor that handles PNG files by selecting Other and browsing for the application executable. Non-portable (installed) image editors will work, but their location may vary from computer to computer. If your choice is no longer valid, PAM Theme Builder will prompt you to change it.

Start by choosing Edit>Background to open the background.png file. Change the file as you please, save it, and then choose View>Refresh in the PAM Theme Builder app to see how it will look in your theme. Leave your image editor open until you are done editing all your images – it's just easier. Continue editing any other component images you'd like to customize. There's also a batch open screen to open multiple images simultaneously.

You can show or hide different things in the display by choosing them in the View menu. When you choose to show or hide the Chrome or Background images, it automatically updates the PATheme.ini file.
You will also need to set the colors of the fonts and the background, and other options that are in the PATheme.ini file.  The link Open INI Editor expands the view to show the corresponding PATheme.ini file in the INI Editor. Use the color pickers to select colors – the display and the ini file are automatically updated. Note that the background color, being the bottom layer of the theme system, only shows if the background image is hidden.

The last step is to edit the Theme Details, which again automatically updates the PATheme.ini file and to package the theme using File>Package Full Theme. If you want to rework your theme further, simply re-open the theme to edit it again.
You can also package only the files you've changed using File>Package Partial Theme.

Menus

File Menu
New – Loads a new default PAMThemeBuilder theme.
Open Theme – Opens a portableapps.com theme in *.patheme format, and refreshes the screen to display the
loaded format. Overwrites the current theme.
Package Theme – Saves your work to the *.patheme format.
Package Partial Theme – Allows you to select only the images you want to include in your theme package, and saves your work to the *.patheme format.
Open IconPack –  Opens a zipped folder icon collection.
Package IconPack –  Saves just your folder icons to a special zip file
Reset to Default Theme – Loads the default PAMThemeBuilder theme. This is not the same as the
Portableapps.com Platform default theme.

Edit Menu
Image Files – Used to auto-open the theme image files directly using the portable image editing app that is set in Preferences. Allow the first image to load fully before opening subsequent files.
Batch Open Images - Open some or all images at the same time.
Preferences – Used to set the portable image editing app that auto-opens the theme image files. Three official portableapps.com apps are pre-configured: GIMP, Inkscape, and OpenOffice Draw. You can also browse for other image editors, or select none.
Explore Theme Folder – Browses the Theme folder which contains the theme image files and PATheme.ini.Useful to open image files in non-portable editors..

View Menu
Refresh – Reloads all images to the display after editing the image files.
Chrome – Used to show or hide the Chrome overlays. This updates the Patheme.ini file.
Toggle Background – Used to show or hide the background.png file. This updates the PATheme.ini file.
Toggle Progress Bar – Used to show or hide the app_progress_background.png file.
Toggle Personal Pic – Used to show or hide an example personal picture.
PA Platform, No Apps, Normal –  Shows the menu as if no apps were installed, and you are not mousing it.
PA Platform, Full, Normal – Shows the menu as if a full menu of apps were installed, and you are not mousing it.
PA Platform, Mouse Hover –  Shows the menu with the alternate "hover" images for the buttons.
PA Platform, Mouse Pressed –  Shows the menu with the alternate "pressed" images for the buttons.
NetBookMode – Removes the title bar and borders to fit into a NetBook Screen of 600px height..

Open INI Editor
Manually Edit INI – Unlocks the editor window for manual editing of the PATheme.ini file. Locks Theme Details and Color Picker functions.
Save PATheme.ini – Saves the contents of the editor window to the PATheme.ini file and locks editor window.  Unlocks Theme Details and Color Picker functions.
Default PATheme.ini – Loads a new version of the default PATheme.ini to the editor window.
Theme Details – Edit the theme details to personalize the theme in the PATheme.ini file. The Name is displayed
in the Portableapps.com Platform.
Color Pickers – Use the color pickers to select font and background colors in the PATheme.ini file.

PopUp Menu
Contains commonly used commands from the main menu..

Tips and Tricks

Package only files you need
Not every theme requires that you package every image in the Theme folder into your .patheme file. You can leave out files that you want to display as the default from the menu. You can select the files you want to include using File>Package Partial Theme.
Of course, you can always just package the whole theme, and you can be sure that your final .patheme file will look EXACTLY as it looks in the PAM Theme Builder.

If you are concerned about space: A full custom theme file is anywhere from 100 - 500 KB. If you just include the PATheme.ini file and the background.png, the theme file is about 5 KB