This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
SecondSight adds some nice features; but, it is known to be a power hog. Most likely, your system is crashing due to noise glitches on the +5V and/or +12V power busses. The fix is to fatten power supply leads and, probably, add on-motherboard +5V and +12V jumpers to a couple Slots. Details are supplied in the POWER FAQs (csa2POWER.TXT).