April 30, 2015 at 3:18 pm #22167
First off, your page size should be 3200 x 800 pixels, not 3400 x 800. You may want to start with the EggBot template as an example.
Can you please say what the issue is with changing the dimensions? At the “standard” 90 pixels per inch, that template works out to ~35.5″ wide– it should not get to 40+ inches.