Increase the gap between the tables, 70 seems about right 
start_y => $boty - 70,

[download]
Update : If that doesn't work, try increasing the start_h, next_h parameters and use $nextpage for the second table. 
my ($nextpage, undef, $boty) = $pdftable->table(
     $pdf,
     $page,
     $some_data,
     x => $left_edge_of_table,
     w => 495,
     start_y => 750,
     next_y  => 750,
     start_h => 750,
     next_h  => 750,
     padding => 5,
     padding_right => 10,
     background_color_odd  => "gray",
     background_color_even => "lightblue",
);

$pdftable->table(
     $pdf,
     $nextpage,
     $more_data,
     x => $left_edge_of_table,
     w => 500,
     start_y => $boty - 10,
     next_y  => 750,
     start_h => $boty - 10,
     next_h  => 750,
     padding => 5,
     padding_right => 10,
     background_color_odd  => "navy",
     background_color_even => "red", #cell background color for even r
+ows
);

[download]
poj

In reply to Re^3: Making PDF Tables by poj
in thread Making PDF Tables by Anonymous Monk

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