This appears in the following page:
https://docs.coronalabs.com/guide/programming/02/index.html
The section where I think the error is, is "Including Images".
In this section, the dimensions is/are specified are: 112 x 334.
I believe that it should be 344 instead of being 334.
Why I think so:
When I add all the heights specified in the "Loading Image Sheets" section, it adds to 344.
More information:
Please look in the section "Loading Image Sheets".
Within this section, there is a long/big snippet of code (around 35 lines of code), that talks about frames.
In this snippet, the various heights are 85, 83, 97, and 79.
They add to 344.