Unless you have a specific rule set to disallow/terminate that process, Lasso would not shut down your security software. It would never do something like that.
I recommend you reset all config to defaults (bottom of Options menu), just in case you do have some problematic rule in place. If you have a bunch of rules you want to keep, first export the INI config file (see File menu), so you can restore them later after determining they are or are not the cause.
A Blue Screen of Death (BSOD) can only be caused by kernel mode code - device drivers. Process Lasso has none.
That means it Process Lasso can NEVER directly cause a BSOD. Something else was doing that.
I *will*, however, set up an Avira test bed just to be sure they haven't added some crazy tamper-protection technology that is malfunctioning. It'd be their bug in such a case, and pretty unlikely - but will do my due diligence.
Thanks for your support!