Hello,
there were some errors when I ran a test upgrade from 4.9.5 to 5.1.4, a few were SQL provider errors pertaining to a sproc that I recognise as one of mine 
and then there was one that's described as "00:00:38.391 - Executing Application Upgrades: 05.00.00 Error!" Can someone point me to the file that may have a better description of the error please? Actually, it would be really handy if the word 'error!' in that message could link to the log for that message.
Subsequently , there was this error: "00:01:04.459 - Installing Package File HTML_Community_05.01.04_Install: Error!" which I track down as "Cannot insert duplicate key row in object 'Packages' with unique index 'IX_Packages'." The app then restarts and I find "Parameter count does not match Parameter Value count" errors in the log from the instances of HtmlModule.ascx on the page.
I'm not sure what caused the duplicate key error message, and I've seen a couple of posts and Gemini entries that appear to relate to this issue, but I'm unsure of the steps that I need to take to resolve it before upgrading my live site, or if there is a fix that I need to apply to my live site once I've performed the upgrade.
Your advice would be greatly appreciated, many thanks.
Barry
PS Fantastic amount of logging for this upgrade, thank you.