Note that you should never 'downgrade' your software version, as this will cause problems in cases where a later software update has updated the device firmware to a later version than what the software expects to find. It always is a good idea to use the most recent software version even if it is a beta.
Current version V2.7.3 7/10/2019 (32 MB) release notes
Current version V4.4.2 7/10/2019 (32 MB) release notes
Current version V3.5.2 1/21/2019 (474 MB) release notes
Reduced size version (43 MB)
Current version V1.0.9 9/14/2015 (13 MB) release notes
TractionControl software is built into SManager, KManager and FlashProManager. Only download this version if you are using a different engine management system.
USB Device Drivers
These are standalone installers with the USB device drivers for Windows XP, Vista, 7, 8 & 10. Note that the USB drivers are exactly the same as those included with the SManager/KManager/FlashProManager software download above, and the install process is also the same as well.
S300 USB Drivers (8MB)
KPro USB Drivers (8MB)
FlashPro USB Drivers (8MB)