Using 1.8 rc2: Execpi tags will only run if 2 or less if/then/else & while statements are used. Else it displays nothing. I must use a separate $execpi to use 4 of statements. However, if a 5th or more are desired, 1.8 rc2 displays issues calling the stdout of the scripts. Sometimes the 5th will be displayed without statement 3, and various other combinations.
Using 1.7.2: One $execpi can be used to call everything.
Could you please include the output of "conky -v", the smallest configuration file possible where you experience your problem, the output that you get, the output that you think you should get and if execpi is calling a script, the contents of that script.