The guide tries to jump to a "farm_thorium" label in the 225-300 section that doesn't exist. Here's a quick fix that should work until it's fixed in the guides and updated. This affects both the Alliance & Horde Professions guides.
1. Navigate to your WoW/Interface/AddOns/ZygorGuidesViewer/Guides folder and open the ZygorProfessionsAlliance.lua file with your favorite text editor
2. Search for: farm_thorium
3. Replace with: jc_225-300_farm
4. Save the file and exit
1. Navigate to your WoW/Interface/AddOns/ZygorGuidesViewer/Guides folder and open the ZygorProfessionsAlliance.lua file with your favorite text editor
2. Search for: farm_thorium
3. Replace with: jc_225-300_farm
4. Save the file and exit