To test SmartPanel application, you need to print a test panel first. Download the panel PDF file attached below this article and print it on A4 or Letter paper.
Make sure that the panel doesn't get stretched or shrunk during printing, as panels with unexpected sizes or aspect ratios won't work properly. The panel size is shown on the PDF and should be checked after printing. Errors in size larger than 2.5mm / 0.1'' should definitely be avoided.
Laser printing is preferred to inkjet. The latter may significantly warp the paper due to the large amount of black liquid ink used.
The printed panel should be affixed to a flat support. Using small bits of double-sided tape is recommended. Glue spray is also acceptable if applied properly. Avoid liquid glue and some glue sticks that contain a lot of moisture. The support itself can be as simple as a flat piece of cardboard (think Amazon boxes) but more durable, flat and rigid materials are recommended. If the panel appears to be warped on its support, discard the warped panel paper and re-print it (this can happen over time with paper panels as the temperature/humidity changes).