Here you find some screenshots of LMMS demonstrating the work with it. If you think there's an important screenshot (yours?) missing, please let us know!
Song-Editor, FX-Mixer, Project Notes and an instrument track window
Piano-Roll (with some selected notes) and Automation-Editor
sample browser, Song-Editor, Beat+Bassline-Editor and some controllers
all tabs of an instrument track window
LMMS on Windows with ZynAddSubFX
3 VSTi-plugins within LMMS
Video on YouTube showing LMMS 0.4.0-Beta2 in action: