Well, your problem seems to come from the fact that foreach file, you print 4 buttons. So you have 4 times as many buttons as you have files - no wonder you get duplicates. Do something like:

print start_from (...);
print table (...);
s/*[\/\\](.*)/$1/ for @files;
while (@files >= 4) {
    print Tr ({...}, map {td (submit (-name => 'file', -value => $_))}
+ splice @files => 0, 4);
}
print Tr ({...}, (map {td (submit (-name => 'file', -value => $_))} @f
+iles), map {td ()} 1 .. (4 - @files)) if @files
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Abigail