I have just upgraded two systems for a local company to use the interface controller. The initial feedback has been very good but they have one comment. Would it be possible to add an easily accessible 'Repeat previous file' feature? This is because they often need to run the same gcode file many times when making batches of components. At the moment it can be a slow process to scroll through the file list each time to find the correct file, especially when there are a lot of files on the USB stick. Maybe the simplest way to implement this would be to automatically highlight the previously opened file when the file list is displayed. Colin.
In the meantime, a couple cheap flash drives (per-job, nicely labelled) could help them be more organised too. Rather than lots of different jobs on one drive, hand the operator the day's job on a fresh drive and let him go to town batching it out. Come back when its done, put the drive in the "done" tray, and pick up the next jobcard with a drive prepared for it? In an industrial setting little workflow changes can massively increase productivity and lower the rate of mistakes