Installshield LE: -4340: Internal Build Error, solved (somehow)

Thanks Flexera for the complete lack of support on this error... Well, my research had me understand the following:

• The setup build crashes at a step which should write this in the log, but doesn't:
  Searching project for extract-at-build components...
• It's component related (ocx?).
• In my case, I have home made components (User Controls) in my project. They may be the cause.
• In my case, it wasn't a dependency problem.

By repeatedly cleaning and rebuilding my projects individually, the error SOMEHOW went away. I couldn't control the problem so that's all the information I have. I hope it helps.