MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
The STL files are fine. The gcode is created by the slicer software you use. The issue is either bad slicer software, or possibly a bad SD card. Creality has had issues with the SD cards having corrupt memory. Try a different slicer, and/or try a different SD card.