First, really nice game! And available for Linux too, yes!
So here's a small bug report, when the mouse pointer is hidden (some dialog is in progress or some cutscene) the mouse turns into a small white box (the size of the normal game pointer). Strange thing is I cannot take a screenshot because in the shot it ends up as the normal os mouse pointer. I am using Linux Mint 19 (based on Ubuntu 16.04 x64). Maybe someone else can confirm this behaviour. After the cutscene/dialog the pointer correctly turns again in the custom game mouse pointer.