I'm still stuck with version 4.1.5 and many many MANY error screens later... I thought once I'm done with my last project in 4.1.5, I'd like to upgrade and yes, I already payed so no, no BS.
Yes, I am quite aware of that.WARNING, you can not upgrade a 4.1.5 project to the 4.5.6 !
The 4.5.6 needs to be downloaded, and intalled in a separate folder... and you will have to start a new project in 4.5.6. You can not open a older version project with the new version.
(but you can export/import tilesets maybe).