Configuring Nuget pack for prerelease on VSTS - nuget

Question

Note
If there is an easier way to create prerelease packages please let me know!
I am using Visual Studio Team Services and have setup a nuget pack and publish step.
I have a build variable called $(BuildSuffix) that allows me to tag build-specific variables onto the end of the build number format like so
$(Build.DefinitionName)_1.0.$(date:yyyy)$(date:MM)$(date:dd)$(rev:.r)$(BuildSuffix)
The idea then is that I can set $(BuildSuffix) to -beta so that my final build version might be Build_1.0.20170119.2-beta.
According to the nuget documentation here, appending -beta to a build number will create a prerelease package. The build in VSTS comes out with -beta appended but the nuget pack stage never seems to contain it. It always comes out as the exact version number but without the -beta tag.
My nuspec files look like this:
<package >
<metadata>
<id>MyCompany.Data</id>
<version>$version$</version>
My NuGet package step looks like this:

Answer 1

After some research and bashing my head against a brick wall I figured out how. You have to:
Configure a local Build Agent
Install Nuget CLI
On Nuget Packager Task set Path To NuGet.exe to the NuGet CLI
Set NuGet Arguments on the same screen to -suffix beta

Answer 2

With new NuGet task(version 2) you can specify Additional build properties and there you can pass your custom build number directly instead of using -suffix NuGet argument. Additional build properties are substituting $token$ with supplied value in nuspec and you are free to change whatever you want in there.
I also see it on your screenshot, but I never tried to use it like this with older NuGet tasks as those are deprecated now.
Maybe it will be helpful to try import NuGet Packaging Task Group definition I am using on my private projects. Check it out Here.