Debug logging and tracing with Automated Deployment Services (ADS)

I'm nearly bald this morning. Last Friday I had what was nearly a full head of hair. Long story, but it all revolves around a series of problems I've been trying to resolve with Automated Deployment Services. I've been trying to locate the information which I once had to hand, but have had big trouble finding again (it doesn't appear to be in the ADS Help, unless you know better). I'm attempting to add some drivers to the Network Boot Service (NBS) in ADS, but the drivers still weren't being loaded correctly. I see plenty of blog entries on their way about the issues I've found and resolved, but while I've now found the information, this seems a good time to record it...

At the bottom of KB 841550, how to turn on logging is described in all it's glory:

For additional information about the driver installation, turn on logging. If you turn on logging, a file is created in the following folder:
Drive:WindowsTracingAdsbuildsvc.log
Note In this folder, Drive is a placeholder for the drive letter where Windows is installed.

To turn on logging, follow these steps:

1. Log on to your computer as an administrator.
2. Click Start, click Run, type regedit in the Open box, and then click OK.
3. Locate and then click the following registry subkey: HKEY_LOCAL_MACHINESOFTWAREMicrosoftTracingAdsBuilderSvc
4. Right-click under the last value in the right pane, point to New, and then click DWORD Value.
5. Type EnableFileTracing, and then press ENTER.
6. Right-click EnableFileTracing, and then click Modify.
7. In the Value data box, type 1, and then click OK.
8. Close Registry Editor