It took about 4 days to fully sync my Dopecoin v3.0.2.0 wallet from scratch. Anyway, the lag problem seems to be tied to minting, when I unlock for minting, the wallet become unresponsive, lock wallet, all is ok.
Thanks for this information Grimnir! Working on a fix .
Hate to offer conflicting info but for me its unresponsive even when I'm not minting. I mean, I haven't been minting in over a month and am unable to. :/