Error exporting asset: Unable to locate the streamed data file. Make sure to open it inside the application.
UABE failing exporting - and I have no idea what this error is saying.
Occasionally succeeded, but no idea why.
Any info about how to fix it would be very appreciated.

I recommend you just use AssetStudio for exporting Texture2D files (and definitely for meshes)
While AssetStudio is an alternative, it struggles with larger file-counts. I'm mostly using UABE for editing and use the exporting feature to check on files i've changed. For some reason, when it fails exporting textures, it also fails modifying textures (instead just crashing rather than giving any errors).
Have you opened the resources.assets.resS file in UABE?
Regarding the program crash, could you provide some more details, such as the game?