Cas Demo Black Screen (with llama face)

Another quick update: I managed to get the sims3 package files to become package files by selecting the sims4 demo as the programme to open them with. This didn't solve the problem, there is still an incredibly long loading time from when you click the desktop icon to when the first screen loads up. Then I get the video showing the CAS tool and sims and then it goes black with the same symbol when you right click. I thought changing the packages would have worked but what I did didn't seem to make a difference.