The first warning you've posted is innocuous and can be ignored. It's just informing you that using ray-tracing will be really time-intensive since it's working on the CPU and not the GPU. It also tells you how to get ray-tracing on the GPU instead. Follow the link it mentions.
What is the exact version number of AE you're using? 11.0.4? 12.2.0?
The second warning is telling you that AE is trying to write files to a certain directory, but the permissions are set incorrectly on that folder. Set permissions correctly or tell AE to point its cache and such to a different location.