First things first. Patch it to 7.5.3.
Thank you for your reply.
however, I am still concerned what to do with your advice... would you mind explaining it?
Your crash report indicates you are running version 7.5.0, the unpatched initial release of CS5.5. There have been two service updates to fix bugs, so you need tin stall the latest patch, 7.5.3, before we can do anything more to help.