okay, if $DEBUG_OP_ADD_COVER_PHOTO = 0, my server returns status: 500 and apache2 error log says: malformed header from script 'index.pl': Bad header: <br><br><br>

the above error doesn't make sense, because nothing is being printed to STDOUT at this point

if $DEBUG_OP_ADD_COVER_PHOTO = 1, I can then print the error given by File::Fetch: could not retrieve file: Command failed:

this one just lacks information

EDIT: Oh, i think i figured it out. omg, i feel so dumb. body of an if statement much further on is missing $output .= starthtml(); and thus, negates this whole issue. face palm with both hands, does walk of shame.