Plugin doesn't work with large tables

[Blodarn]

Right now, the plugin only allow columns from A to Z. I tried to replace the array $columns with :
protected static $columns = array(
'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
'aa','ba','ca','da','ea','fa','ga','ha','ia','ja','ka','la','ma','na','oa','pa','qa','ra','sa','ta','ua','va','wa','xa','ya','za',
'ab','bb','cb','db','eb','fb','gb','hb','ib','jb','kb','lb','mb','nb','ob','pb','qb','rb','sb','tb','ub','vb','wb','xb','yb','zb'
);

No success :(