BUG: searching this string

Hi, we always use your plug in but this time we put this string to look for:
Population: [population-339]

and it should be substituted by this one:
City: [poblacion-339]

but when we run the search:
Warning: preg_match_all(): Compilation failed: range out of order in character class at offset 31 in /var/www/vhosts/everbit.es/newsite.everbit.es/wp-content/plugins/search-and-replace/inc/FileDownloader.php on line 213

thank you!