Hello Unregistered,

there are always two kinds of connection, first there is the gnutella network on the netwok tab. Search requests are routed here.
Then there are uploads and downloads, but download doesn't always mean outgoing as it is possible to send a push request over the gnutella network so you are connected back from the other side to receive your request. Uploads and downloads are not part of the gnutella network, so you can press disconnect while a dowload or upload is performing.
This principle is utilized on all gnutella servants.

Helge