I think knowing wha the security error really was would be helpful.
Do you mean about the alert dialog? It only appear once and never appear again. I remember it appears when I tried to run another Flash Builder project in Flash Builder 4 which has access to webcam to do AR thing using FLARtoolkit and papervision. I never get the alert dialog again even if I rerun the AR project, after restart PC, or relaunch Flash Builder. But now, I am facing Stream Error problem.
How can I overcome it? Thanks.
Try using merged-into-code option for AIR apps.
what is that? Can you please explain better? Thanks.
You're advised to check and change (if applicable) your project settings for AIR application and for that Flex-based application loaded at runtime to use "Merged into code" linkage option for "Frameworks linkage" option in project settings:
Assumed on description of issue you've faced one could think that on some occasions your loaded Flash movie (.swf) tries to apply dynamic linking trying to load some RSL library first from application domain (app/....) which is local path and then fails.
AIR based apps should use "Merged into code" option (and that is default value set in project template for AIR based apps in Flash Builder),