There are some instructions embedded into the tool in Sitefinity 4.2.
However, Josh Morales is also preparing a more detailed migration guide. I expect this to be published next week.
Also, I did a video
on this subject a few months ago. The video covers the CodePlex version of this Migration Tool though. Which means it required manually compiling and installing. Consequently, big parts of that video are no longer applicable. What is applicable is the installation of the DLL files into the Sitefinity 3.7 web site.
I realize our guidance on this (at the moment) is insufficient. Check out the embedded instructions and the video and let us know if you have any problems.
It worries me when I read "it's very urgent". Given the current state of the migration tool (Alpha) it doesn't lend itself well to migrations with a tight deadline.
That being said, we're very willing to help. Are you getting any errors? If so, what are they? Toss us some details and we'll help.
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