Everytime I load up Tixati half my applications lock up, including tixati.  Well, tixati runs, but is unresponsive.  I can not interact with programs like Dexpot at all.  My browser will crash randomly. And I'm sure a whole host of programs lock up in a similar manner, I just can't tell because Tixati renders my machine unresponsive and therefor unusable.  

Basically, what happens is I can move my mouse and navigate Windows, but applications, including Tixati, do not respond or are very slow to respond to any interaction, mouse clicks or hotkeys.

My torrent files are all located on a linux PC connected locally via ethernet.

When I close tixati my system returns to normal.  I'm kind of hoping that there is some setting that I may have overlooked.

I'm using Windows 7 64bit Ultimate w/ CPU 3.4GHz AMD Phenom II x4 and 12GB RAM.

Try running only one torrent from local hdd.

It sounds like multiple anti virus and or anti malware programs are scrutinizing the tixati packets. Meaning they are stealing all of your computers resources.

I just built a very similar system, a little less powerful.  

AMD Phenom II x4 945 CPU at 3.0 GHz, 8GB RAM  Win7 Pro

I haven't see anything like what you describe. And I run a huge number of other apps while tixati chugs along seeding 401 torrents, maxing out my set 192 MB/s UL bandwidth.

One difference is all my torrents are on a local RAID, not remote. I'd explore that area first I guess.