V0.6.21

 of Stormworks: Build and Rescue was released on April 26th, 2019.

V0.6.21

 * Feature - Added modular tank track components (3 sizes of drive wheels and 3 sizes of regular wheels)


 * Fix - Rebalanced costs of several tech tree research items
 * Fix - Research view no longer hidden when "infinite stock" is enabled
 * Fix - Research view hidden when "unlock all components" is enabled
 * Fix - Missions no longer reward RP when "unlock all components" is enabled
 * Fix - Fixed research time not updating for host in multiplayer
 * Fix - Added confirmation dialog when beginning research
 * Fix - Fixed fans and underwater propellers having toggleable physics

Source

 * Steam Community News