Factorio Forums

Currently, when you click 'Install Mods', the game appears to lock up. This happens because the cursor does not change from an arrow to an hourglass. I suggest they follow standard GUI guidelines and change the cursor from an arrow to an hourglass. Alternatively, the game could display something on the screen to provide info that the 'Install Mods' button was clicked.

This suggestions is the top of the iceberg about mod-handling - which will eventually be fixed in 0.16.