You need the original password generated when genkey was run. Since you have access to the Roku account, you can download the last package file. Using that and the original password, you can rekey your development box so that new packages will be keyed to the existing password/key. If you don't have the original password, there's no way to rekey your development box to the old key and there's no way to preserve the registry associated with the channel when you upload/publish a new package.
-JT
Roku Community Streaming Expert
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