Do you experience problems during downloading?
Check your connection in Status and Interface settings window.
Use Test Server in Config > Servers.
We will probably ask you to do a test using only basic settings.
Do you experience problems during repair or unpacking?
Enable +Debug logging in the Status and Interface settings window and share the relevant parts of the log here using [ code ] sections.
The changelog mentions that support for X-DNZB-Failure header was added in 0.7.17Beta1. Did this feature not make it to 0.7.17 final? I don't see any mention in the code for this header information. I've written my own indexer, and it'd be nice to be able to report broken/bad NZB files.