If you check a second time a torrent that has already been checked by gtorrenviewer (without closing it), don't check chunk that were good. and just skip them to only check the ones that were bad
There is no good reason that a chunk that was downloaded and that passed validation became all of a sudden bad; execpt hdd malfunction or filesystem corruption. This feature speed up any new check after the initial one, especially if there is many good chunk already.
If you consider implementing this, then you might also want to avoid also to have to choose the directory of the torrent files every time we click on Check button
Once is enough.
It's as if this has not been considered as a way to use gtorrentviwer: ie. check mutilple time the same torrent