I guess that Workbench is something new about Tortoise HG 2.0 so I'm not familiar with it and I guess my instructions are not up to date with that version. I'm currently using Tortoise HG 1.1.9.1
No doubt it has the same functionality available but you'll have to poke around and see where they moved things. I'll upgrade when I get a chance but my current version is working fine for me so I'm in no rush.
Best,
Joe