Ender SE

Hi, 3D newbie here, having a few teething problems. So, all set up and ready to go, using the SD card to transfer files from the creality software. Printed one of the free files, a yes/no dice and it printed great.
However, tried a few other files and it’s goes through the printing motions but no filiment. The temp on nozzle usually reads for example 200/200 while printing BUT a lot of the time I’m getting 200/0.
Clearly there’s something going wrong, I’m thinking the files aren’t good

ALL help welcome :+1: