COREL A.R.M for CorelDraw12

Dear CorelDraw12:

I am at work using CorelDraw12 on a daily basis. I am making up a 60 page price book and copying and pasting the data from a last year 60 page price book (both done in CorelDraw12)

After about 1 to 2 hours of producing, I get the infamous COREL Application Recovery sign: APPLICATION IS UNSTABLE!...then it all closes down and CRASHES!  Why is this happening?

Thanks,

Gary