Using an anti-virus software like Avast...
If you use an anti-virus software like Avast it will not enable you to use Shadowforge sandboxy. Which means, that you can not save files such as animation frames to any folder you want.
If you enjoy Shadowforge, please use a Shadowforge friendly anti-virus software. Windows comes with it's own firewall so unless it's underperforming you will not really need an independant anti-virus software. This is my opinion, but if you want to use Shadowforge with sandbox you can not use anti-virus softwares like Avast.