Lost my files after installing WPMU DEV, is there a conflict with WP Download Manager?

Hello,

I purchased and installed your WPMU DEV package earlier this month. I have installed no themes but have installed a few of your plug-ins, though I think I have only activated one of them. In any event, I noticed that all of my files that I uploaded to my site to make available to my viewers to download have now disappeared. No other changes have been made since your plug-in(s) were installed.

Is there any known conflicts with WP Download Manager?

I look forward to hearing from you.

Thank you,

Mark