How to customize a plugin whilst maintaining ability to upgrade

I am currently working on a major update to one of my WordPress plugins.

The plugin lets the user choose from several available skins. Quite often I get asked to create a custom skin. To prevent this skin from being deleted on upgrade I have to use a WordPress hook to disable automatic updates for the plugin. This is obviously not ideal as I would want them to still be able to update the plugin. The problem is the way WordPress handles updates – it simply deletes the plugin folder and installs the new version. Thus removing files which were not actually part of the old version.

Currently the only way I can get around it is having two skins folders – one in the plugin folder and one in the uploads folder – is this really the only way I can offer this to my users?

Many plugins use /wp-content/custom-plugin-folder/ to store customized plugin data (WPTouch comes to mind).

Just use the constants WP_CONTENT_URL and WP_CONTENT_DIR ^Docs to check for the existence of your folder and retrieve any available skins.

The following article, although not directly related to this Question, explains the importance for plugins/themes to search for translations first in the wp-content/languages folder before loading its own packaged .mo files. It’s a worth read and hopefully you’ll apply the concept in your next release 🙂

Loading WordPress language files the right way
^{http://www.geertdedeckere.be/}
I would like to point out that is important to load custom user language files from WP_LANG_DIR before you load the language files
that ship with the plugin. When multiple mo-files are loaded for the
same domain, the first found translation will be used. This way the
language files provided by the plugin will serve as a fallback for
strings not translated by the user.