This is interesting. The problem here doesn't look like it's in the actual build task itself, it's in the engine. The thread being used by the engine is being tied up by something for a full 12 minutes. Because the completion of the task is reliant on the engine to process it, it gets held up.
We need to get a detailed log of what the engine is doing when it locks up like this. Unfortunately because of the nature of the problem, the NCrunch bug reporter won't really work for this, so it'll need to be a manual extract.
To get an extract of the log, you'll need to do the following:
1. Turn on the 'Log to output window' configuration setting
2. Set the 'Log verbosity' to 'Detailed'
3. Everything will run very slowly
4. Open Debug->Windows->Output->NCrunch Output Window
5. Start things up so that NCrunch falls into the 'locked' state
Whatever is showing in the log at this stage is of importance, as it will tell us what the engine is doing. I'm willing to bet that whatever has the engine this busy is probably logging things like crazy, so it may be quite tough to get a manageable extract from the log. If you can copy/paste the contents of this into a file, ZIP it up and
submit it through the contact form I should be able to analyse it from here.