I have 11.000 documents in my downloads section of my vbulletin big board. I am using LDM for it. Links & Downloads Manager was downloaded thousands of times on vb.org so there must be others who encounter the same issue.
I do see requests for an importer for Downloads II which is the other popular resources solution for vbulletin. I'm sure if an importer would be built it would be useful to also include support for IP.Downloads.