yes, you can use it for another challenges, you need only tag it with the same or different config.
The current config for hte gc581qn is
-
{
"types": 6,
"states": 6,
"cachetypes": [
"Traditional Cache",
"Unknown Cache",
"Multi-cache",
"Event Cache",
"Earthcache",
"Letterbox Hybrid",
"Cache In Trash Out Event",
"Wherigo Cache",
"Webcam Cache",
"Lost and Found Event Cache",
"Mega-Event Cache",
"GPS Adventures Exhibit",
"Project APE Cache",
"Groundspeak Block Party",
"Giga-Event Cache",
"Groundspeak HQ",
"Groundspeak Lost and Found Celebration"
],
"country": [
"Germany"
]
}
so, if your cache is identical, you can use it as-is. If not, you can modify it for your configuration.