Latest is 2.6.3 
All the changed files for each release are listed at the end of the readme file: https://github.com/mcrossley/SteelSeries-Weather-Gauges/blob/master/ReadMe.txt
There are a lot of changes between 2.4.4 and 2.6.3, I’d install it to a new folder and start again in parallel with your existing install. Get the new version working and then cut over to it.