I decided to try Tixati today, abandoning Deluge for good (its daemon had a tendency to hang without crashing, and the only way to notice it was to see if the current transfer speed varied or stayed fixed).

So when I was importing my entire library of torrent files, and painstakingly show Tixati where the files for each torrent was, it started checking the file integrity. So far so good, the speed was OK and everything seems to work. But then I started noticing my DL speed peaking, and this was on torrents Tixati was currently checking.

Is this a bug, or is this how Tixati is programmed to behave? I don't understand where the data goes either, because the check completes and download stops, and all files work. So why does it start downloading a torrent that still isn't done being checked? Seems like a ridiculous waste of bandwith, especially considering that all the 150 torrents I added was complete.

A "workaround" for this was stopping all torrents, and checking one at a time. This only allowed for the current torrent being checked to download, which finishes before a substantial amount has been transferred.

Edit:
Here's a screenshot of it happening: http://i.imgur.com/jRhOR3v.png
This is NOT good for any sites that tracks UL/DL ratio.

Windows 7, x64. The data for these torrents are located on both an internal 5400rpm drive and an external 7200rpm USB3.0 drive, and I don't use a page file.

I noticed the same thing as well after files were relocated outside of Tixati and were later corrected within it.  

Just to add a bit more information: When it finished checking a torrent, after having downloaded what it could during that process, the progress would be set to 99% and some pieces would be incomplete.  So that seems to be where the data is going... it is overwriting some of the completed pieces, at least until the check finishes and it finishes downloading the missing bits.

Yes, for now when adding a complete torrent it is better to Stop that torrent on Loading Transfer window and Force Check manually when not running (right click a torrent > Local Files > Force Check). For large amount of torrents you can first load them stopped and later Force Check all of them.

I'm guessing "checking" is a torrent state, so a simple check for it before starting download shouldn't be hard to implement.

Luckily this is far from an app-breaking bug, because I'm really starting to like Tixati. I drooled when I first opened the settings window and seeing all the things I wanted to personalize, good job guys!