When printing with a Print Environment or Cut Environment that uses a file interface (E.g. Zuend), the driver will output a .ppl file instead of the required file type like .prn, prt, .cut, etc. The .ppl file is an Ergosoft internal intermediate file. It is not usable by the printers respective front end. 

The .ppl format is the temporary raster file format that Ergosoft uses. If you are seeing .ppl files in your output folder, the reason is most likely that the output folder was accidentally set as the spool folder and the RIP is now writing its temporary files into the output folder. 

The solution to this is simply to close all Print and CutQueues, then go into your Print- or CutEnvironment under Output Device, click the Edit Button next to the PrintQueue and edit the settings. Make sure that the Port field has the actual output folder and that the Spool Folder field is the path to where your temporary spool files should go. Save your changes then start the Print- and/or CutQueue again.