Kart Racing Pro release13d available:
http://www.kartracing-pro.com/?page=news
It is possible to download a patch at this link, to avoid having to re-download the whole installer:
http://www.kartracing-pro.com/downloads/kart.exe
To install it, simply overwrite the executable in the Kart Racing Pro installation folder.
Full download:
http://www.kartracing-pro.com/?page=downloads
( download mirrors would be extremely helpful and welcome )
How to update: http://forum.kartracing-pro.com/index.php?topic=3597.0
Release Notes
Release13: http://forum.kartracing-pro.com/index.php?topic=10969.msg62220#msg62220
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DrivingItalia download mirror https://www.drivingitalia.net/files/file/3451-kart-racing-pro-by-piboso/