All I can find on troubleshooting the JS errors are old and the links no longer work.
Unfortunately, deleting the cache may work for some but is definitely not a 100% solution. I have deleted the cache several times, as well as deleting the entire configuration folder.
Based on all of the forums I've found this error mentioned on, this problem seems to be going on for years. I'm surprised that Adobe hasn't created a solution/patch/update to fix this problem.
I haven't found a working solution either, having tried other "fixes" without success.
This happened initially with DW CS6, so I switched down to CS4. Same error messages regarding "dwscriptsExtData.js"......
If I find a solution, I will update.....