I suspect I know what you're talking about. Sitefinity releases and SDK releases are not always perfectly aligned. If you're following the internal builds, then they are even more prone to being mis-aligned.
I've also tried upgrading the SDK projects and encountered similar issues to what you're describing.
Here is the deal:
The SDK solutions (Charity, Corporate, etc.) contain multiple projects. These projects reference assemblies in a shared ~/Dependencies folder, instead of the ~/bin folder. Sitefinity's upgrade tool only updates the assemblies in ~/bin. Consequently, using Sitefinity's upgrade tool on an SDK project doesn't really update the project.
I recorded a view showing how to overcome these challenges:
Your larger point is regarding the 'DLL hell' experience. This is an experience I've had with .NET in general (quite apart from Sitefinity). Do you have any suggestions for how to better manage this experience?
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