Javascript Errors Digital File Pro 2

I am having terrible trouble with this extension. First it crashed CS4. I removed the WinFileCache from my configuration folder. That allowed me to activate it. However, every time I try to use it, I get the following two JavaScript errors. I have tried re-deleting the WinFileCache but still get them

while executing onMouseUp in WA_DFP_FileUpload.htm the following JavaScript error(s) occurred:

At line 428 of file C:\Program Files (x86)\Adobe\Adobe Dreamweaver\CS4\Configuration\Shared\WebAssist\WA_GeneralUI.js:treenODES[newIndex] has no properties

And then:
while executing onMouseUp in WA_DFP_FileUpload.htm the following JavaScript error(s) occurred:

At line 74 of file C:\Program Files (x86)\Adobe\Adobe Dreamweaver\CS4\Configuration\Shared\WebAssist\DigitalFilePro\Liabrary\WA_S BEngine.js:
tParams[loopParams[0]] has no properties

I have had to remove it and go back to DFP1 which works without issue

Am using CS4 on Windows Vista (64bit). Please advise if there is a fix for this

It is not a known issue, so there is no fix available yet. I would suggest posting a support incident. You would have to be willing to reinstall and reproduce the error to go down that route because until we are able to reproduce it or work with someone directly that is able to reproduce the problem we won't be able to find the solution.