That is not where you limit the file size, you inadvertently limited the size of the new folder to 1 GB, and since it set to delete you only have a few minutes of recorded video. Set it back to 95% you're available free space. the file size limit is set in the record tab of each camera
I will change my settings to move to my NAS.If New and Stored are in the same drive then I’d personally not bother moving to Stored.
You have also set Stored to move to Stored?
Also interested in why you need to convert the clips to MP4
Files bigger than 4GB can be an issue with some software (not sure about BI).I Have 6 hours video = around 6GB, I try to convert this big files did not work.