It seems that if your UI scale config make the patch notes modal larger than the window, it's impossible to close. I'll fix that in the next release. As a workaround, you can edit your config file (C:\Users\<username>\AppData\LocalLow\isocon\Isocon\config.dat) and set ReleaseNotesSeen like so: "ReleaseNotesSeen":"|0.7.0|0.7". Thanks for reporting this issue!