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You'll need to ask the people who make EpNamer which drag & drop formats their app supports, or maybe ask them to investigate why it isn't working with drops from Opus. Opus should be putting the standard formats into the drag & drop object (which is a bit like the clipboard) but maybe it's doing things slightly differently in a way which confuses EpNamer. It's difficult to tell which formats EpNamer accepts without the source code to it, but the EpNamer devs can easily see what Opus is offering as the drag & drop protocol means Opus advertises the formats it supports.