These are the test programs for ZEngine, all have the basic controls:
ALT-F4 or ESC- Quit Program
S - Switch Modes (ZImageTest only)
The ZEngine Config File (tests.zcf) file may be manually edited using a text editor to change certain settings.
ZMouseTest - Test ZEngine Mouse Capabilities.
ZImageTest - Test ZImage by drawing several images and a string to the screen.
ZFontTest - Test ZFont by outputting text in different formats.
ZTimerTest - Test ZTimer with three different timers. 
ZMusicTest - Test ZMusic by playing a song, and allowing settings to be adjusted.
ZSoundTest - Test ZSound using various sound effects.
ZRectTest - Test Rectangles, and related collision.
ZParticleTest - Tests the ZSimpleParticle class, this test requires SDL_Image as it uses the .tga image extension.
ZAnimTest - Tests the various types of animation supported by ZAnimation.