Each course is the actual playfield tilemap, decoded from its .mlb map file and
assembled tile-by-tile exactly as the game's blitter does — a 36-tile-wide column of 8×8,
16-colour tiles, in the course's own palette (the isometric look is painted into the tile
art itself, not a 3-D projection). Drag to pan, scroll to zoom; the marble starts at the top
and the GOAL is at the bottom. Tick Slopes (3D) to switch to the course's
height field — the surface the marble physically rolls on, reconstructed from the
Track file's slope regions (the engine's own build_region mesh) and rendered as
a 3-D model you can drag to rotate; height is coloured low→high and slightly
exaggerated to read the gentle ramps. See the
write-up
for how the tile format was decoded.