Terrain.dll CTD

I got one of those terrain.dll crashes this afternoon but not concerned. I noted I had an Error Code 0005 too which is a memory exception error. I was coming into KDCA for a landing in very, very heavy weather (it's raining a lot here in the Wash DC area!) in my PMDG 739NGX. I was just about 100 yards from landing and I know the FMC was doing a lot of computing with all the weather so I attribute it all to a sudden memory glitch while FSX was reading the terrain.dll. I didn't see any loss of FPS and there was no stuttering. Just the sudden message that FSX has to close. Just thought I'd pass on my misfortune and the loss of all my virtual passengers and crew. I'll try again tomorrow when the weather is better. BTW, for the first time since buying the PMDG 737, I noticed the animation of the cockpit crew in external mode. I thought it was neat with the co-pilot occasionally looking at the upper panel and then moving his right hand up to that area as if turning on or off something. The pilot was occasionally observing the co-pilot doing his thing. Very realistic! Best regards,Jim