Inroads crash has damage data in the file... again

After entering the Corridor Trimming Reference, the program has crash, when i reoopen the file active terrain is displayed as an unresolved object. The corridor that was to be cut would disintegrate into individual elements, and the program would collapse when attempting to corridor objects. If I delete the whole corridor, the same elements on which it collapsed remain in the drawing. Is there some way to fix it? This program is more and more frustrating for me, an extreme number of bugs, and very often crashes and from time to time the program completely destroys my work and I can start from backup if any. The Czech version (see the other thread), contains a rendering error that Bentley knows, but he does not anything with him, especially i see everywhere advertising "AUTOCAD Users - Feeling Trapped?". My colleague has AutoCAD Civil, and the program crash max. one time per day.