Customization
You can extend StepMania with various forms of add-ons to customize your gameplay experience.
Add-ons are usually distributed in ZIP files. Your user data folder contains a number of subfolders where custom content should be placed.
Themes are used to customize StepMania's interface. You can download themes from the StepMania forum, as well as other websites; themes compatible with 5.0.12 are also compatible with 5.1. Themes from older versions (SM3.9 and variants, 4 alpha, 4 beta) are not supported in SM5 branch.
Themes are installed in the Themes subfolder of your user data folder. Note that the theme folder placed in the Themes directory must be the one that contains folders such as BGAnimations, Graphics, etc.
Quit StepMania, and check to see if you accidentally have something like ./Themes/Some Cool Theme/Some Cool Theme/. If so, move the innermost folder up a level so that you have a structure like ./Themes/Some Cool Theme/
In SM5 themes are primarily constructed using Lua scripts and an associated API, graphic files, and metrics. If you're interested in building your own themes, see the Theming page on the wiki for more information on basic concepts.
NoteSkins change the appearance of the notes, from standard arrows, to spheres or even bars.
NoteSkins are installed in the NoteSkins subfolder of your user data directory. On StepMania 5.1 and older, NoteSkins only support one game mode at a time, and are placed in subfolders of the NoteSkins directory that correspond to the game they are designed for (i.e. ./NoteSkins/dance/ or ./NoteSkins/pump/ or ./NoteSkins/para/).
NoteSkins compatible with 5.0.12 are also compatible with 5.1. NoteSkins from older versions (SM3.9, 4 alpha, 4 beta) are not supported in SM5.
In SM5, NoteSkins are constructed using a combination of graphic files, metrics, and Lua scripts. You can learn more at the NoteSkins wiki page.
Announcers are used to provide voice clips triggered by specific screens, in-game events, etc. Announcers are compatible with any version of StepMania, for example an announcer created for StepMania 3.9 will still work in StepMania 5.