v2.4

Changes in v2.4

New pieces:

• Various wide track pieces including giant curves, track, tunnel and bottleneck parts
• Track Dish Double 24cm
• Support pieces
• Launcher active element (animated)
• Valve active element (physical)
• Hopper active element (physical)

New materials:

• DPT Marble
• DPT Sparkly

Some pieces were renamed for consistency.