well I'm confused but happy you're up and running - I'm guessing it was your network config, not the plugins

kindly mark the thread as solved (see my sig)

I understand you perfectly – I understand the whole thing less than before... Be it this upnp plugin or just random chance at hitting the buttons in the configuration wildly, but suddenly it worked (I'm just verifying it once more in a nightly test run
Every torrent now downloads as it should, magnetlinks are working, I got about 450 kb/s... So even if nobody knows where some 0s or 1s were in the wrong place I guess my problem is solved

Just like to confirm this issue. After some months of not using Ktorrent, with a distribution upgrade somewhere in there, on a relaunch of the gui there was no activity, on new or months old torrents, complete or incomplete; no seeds, nothing up or down, total zip. But with a couple of ennablings in the plug-in's tab or panel, it started immediately. Confirming it was after ennabling of IP Filter, UPnp and Scheduler plug-ins.