ok it is a .desc issue.
You added double quotes '"' in your map description. Just remove them or replace them by single quotes.
You can copy past the next code. Double quotes replaced by single quotes.
<map>
<name> The Fall of Dresden </name>
<briefing locid="''You guys burnt the place down, turned it into a single column of flame. More people died there in the firestorm, in that one big flame, than died in Hiroshima and Nagasaki combined.'' --Kurt Vonnegut, Jr">map description for modders maps not localized (english only)</briefing>
<music> common/sound/menu/music/es_war_ein_edelweiss.ogg </music>
<modes>
<mode type="gpm_cq">
<maptype ai="1" players="64" type="headon" locid="GAMEMODE_DESCRIPTION_headon">Unlocalized test for this mode on this map</maptype>
</mode>
</modes>
</map>