Acronis Nonstop Backup and Powerarchiver

Win 7 Ultimate 64 bit on Dell 64 bit, TI Home 2011, build 6696

I use Powerarchiver a lot (have done for years), but decided to set up TI Nonstop on my system.

I then found that when I deleted files from archives (zip, zipx) at the first pass they went OK, and on the second, whether the archive was open or reopened, the entire archive disappeared off the disk.

I remembered that I'd experienced similar problems on an XP machine running Memeo Autobackup, so I stopped TI Nonstop, at which point my problems were solved. I'd also been experiencing some other odd problems with encryption and erasure programs, and these also stooped when I ceased Nonstop.

Is it possible to stop Nonstop being so aggressive in its file grabbing? Would, for example, lowering its priority make any difference and prevent this sort of problem?