As of Nuget 2.8 there is a feature to downgrade a package.
The following command entered into the Package Manager Console will downgrade the couchbase client to version 126.96.36.199
Update-Package CouchbaseNetClient -Version 188.8.131.52
Updating 'CouchbaseNetClient' from version '1.3.3' to '184.108.40.206' in project [project name]. Removing 'CouchbaseNetClient 1.3.3' from [project name]. Successfully removed 'CouchbaseNetClient 1.3.3' from [project name].
Something to note as per crimbo below:
“this approach doesn’t work for downgrading from one prerelease version to other prerelease version – it only works for downgrading to a release version”