Clearing content from a table when using Screen1.BackPressed

Your rangedata came back with a table with one row and 4 columns (A2,B2,C2,D2).

I can see that by looking at the screen shot of Label1, where I see the JSON markup wrappers around lists, " " around pieces of text, and , between items of a row match up with how you had filled those 4 cells of your sheet.

If you are unfamiliar with how to read JSON, search the Web for "Introduction to JSON".

Regarding how to extract the proper items from that table and drop them into Labels, this code sequence could be used in the .GotRangeData event:

if length of list (rangeData) > 0 then
   init local firstRow to select item 1 from rangeData
   if length of list (firstRow) > 3 then
      set LabelMarca.Text to select item 1 from firstRow
      set LabelModelo.Text to select item 2 from firstRow
      set LabelPotencia.Text to select item 3 from firstRow
      set LabelDescripcion.Text to select item 4 from firstRow

Notice how I am testing length of list before I go to select items from each list.
I am following the technique of Defensive Programming, where you expect the unexpected.

If you have trouble getting data out of tables, see the introductory articles at