Wolfenstein Tips and my game is freezing

Tips for any of you whose XBOX 360 game is working. But my game crashes and freezes at the last level, "Black Sun." UPDATE. Sept. 9, 2009. THE GAME CRASHED WHEN I HAD 100% OF ALL THE COLLECTIBLES. I ALSO REPLAYED A MISSION BEFORE "BLACK SUN" THOUGH I AM NOT SURE THIS IS A CAUSE. ANYWAY, I PLAYED THE GAME WITH LESS THAN 80% OF THE COLLECTIBLES GOING INTO "BLACK SUN" AND DID NOT REPLAY A MISSION. IT WORKED. SO WATCH OUT FOR THE AMOUNT OF COLLECTIBLES AND DO NOT REPLAY UNTIL YOU FINISH THE GAME. Update. Sept. 13, 2009. Activision suggested that I play from a previous saved game and delete the rest. That also worked. I played the game again, deleting games as I went forward. At the end, I had one saved game and was able to hop into the portal. The "Black Sun" loaded. I completed the game with 100%in collectibles.>

I. The Tips

1. Get the Collectibles- As you play the game, you will find gold, tomes and intel. Unlike the gold in Return to Castle Wolfenstein (RTCW), the gold in this game actually has a purpose. You can use the gold to upgrade your weapons at the black market. Intel gives you hints as to how to complete mission goals. By the way, some intel are not in order, i.e. you might collect intel #5 before #4. This happens at the "Zeppelin" where once you collect the intel from the Heavy Trooper, go through a door and turn around to get the intel on the wall which is number 5. Tomes, which make a humming noise, will upgrade your crystal powers.

2. Get all the Tomes- If you collect all the Tomes, all your crystal powers will be upgraded without having to purchase them. Now, this will take almost the whole game but if you save the mission "Airfield" for last and you should, you will have all the crystal powers for that one, and "Zeppelin." Update: WARNING! DANGER, WILL ROBINSON! There's buzz on the net that getting too much of collectibles will cause Wolfenstein to freeze. I know I have collected everything before the Black Sun and the game froze. I also replayed a mission. I hope Activision solves this problem. See the links for the buzz.

3. Use the Veil, BJ! Using the Veil puts you into an alternate dimension, one that coexists with ours. In this dimension you will see geists or floating creatures. Shooting one causes an energy discharge that can kill enemies. For example, on the "Farm" level at the beginning, you clear some Nazis in front of a stable. Go to the right and you flank a machine gun nest. Turn on the Veil. There will be geists floating near the nest. Shoot one. German guacamole. No more machine gun nest.

The Veil also highlights targets. These include enemy soldiers, and also areas you need to hit to complete an objective. This leads us to...

4. Tips for Defeating General Zetta- SPOILER ALERT! At the end of the "Cannery" Level, you face the boss General Zetta. In the cut-scene, BJ fires his MP40 at Zetta, and the bullets seem to pass through him without harming him. Then Zetta ala "Goldfinger" explains to you that you don't understand. These are hints. Turn on the Veil. You are now in his dimension and your weapons can now hurt him. In fact in the other dimension, he's no longer human. Pretty cool, huh? There are three pools of Veil energy. When you hurt him enough, he retreats to the pools, turns on a generator above to recharge. You will notice a red area on the generator. Shoot at it. It blows up. Do this to the three and finish off Zetta.

5. Get scopes for the rifle and assault rifle. When you can, buy scopes for the Kar98 rifle which turns it into a sniper rifle and the MP43 assault rifle. Now instead of having to move forward to kill you enemies, you can whack them from a safe distance. Scope for the Kar98 is available at the end of the "Dig Site." And the scope for the MP43 is available after completing "Cannery."

6. Buy the official Wolfenstein guide from Brady Games. Okay, I know it costs you twenty bucks. And there may be a free online walkthrough. You can complete all the missions without the guide. But it's difficult to get all the collectibles without the guide. Just remember that the gold is needed to upgrade your weapons. The Tomes upgrade your crystal powers. The guide gives you a picture and description of where they are at. With the guide, it will be easier to collect all the items. WARNING: DANGER, WILL ROBINSON. Again, there's a thread that collecting too many items can lead to Wolfenstein freezing and crashing. See the links below. I don't know if this is true. If I find out anything more, I'll let you know.

II. The Black Sun Freezes

Okay, I've just completed the "Zeppelin" level. Now comes the final mission called "The Black Sun." I'm watching and reading BJ's report. I then start the next and last mission. The load screen says I'm travelling to the Black Sun and as it starts to load, it freezes. Noooooo. Mein Lieben! I try it again and again, it freezes. Not only does it freeze, it crashes. I can't access the XBOX dashboard. I have to turn off the machine. And before you say it's my XBOX, it's not. I know what the Red Ring of Death is. I've cleaned the game disk. I've loaded the game on my hard drive. I've cleared the cache. Nothing works. See above for update.
Currently, I'm waiting for a response from Activision. By the way from a Google search, some of you are seeing the same problem. Here's a forum discussion. Here's another forum. Feel free to comment and let me and others know if you have a solution.