As usually the CPU usage goes up to 50%
then gradually reaches 98/99%, but only when i start
making more and more searches.
Then i've noticed if i keep the searches idle the CPU will not start to rise.

So at the moment the best solution for me is:
make the searches,
start the downloads,
then shut it down and restart,
and complete the downloads with no new searches.
it isn't very convenient, but so far i don't know what else to do.

I'm still hoping the new version will fix this problem,
but having seen that the problem has been on for ages,
i doubt it.