I too have had this issue, been driving me absolutely crazy!!! I found a hack where you edit a couple files and swop two characters around on core/model/modx/mysql/modchunk.map.inc.php
Simply change this:
'rule' => '/^(?!\\s)[a-zA-Z0-9\\x2d-\\x2f\\x7f-\\xff_-\\s]+(?!\\s)$/',
to this
'rule' => '/^(?!\\s)[a-zA-Z0-9\\x2d-\\x2f\\x7f-\\xff-_\\s]+(?!\\s)$/',
But i've now got even more serious issues where wayfinder and getResources output absolutely nothing?
I've got ton's of modx site up and running with no problems like this before. This last week i've had nothing but issues with MODX Revolution 2.2.13-pl (traditional) with a fresh install, i'm using a very simple wayfinder call
[[Wayfinder? &startId=`0`&level=`1`]]
With 5 resources created just to test and get nothing output at all, same happens with GetResources?!
Any ideas what could be causing this, do you happen to know what setup is best for wayfinder to run? Oddly i've updated other sites to the new version of modx and they wayfinder calls work ok on them, I think this is due to it being updates and not first time installs on the new version?
Lee