Add custom path support for the steamapps library

[WoozyMasta]

workaround until I fix the launcher:
create a symlink to DayZ from a custom steam library in the default steam library

[airtonix]

i have dayz on a different drive.

[WoozyMasta]

I need to find free time and an opportunity to do this while we wait for this.

And so you can transfer the game or make a symlink