Ok I tried this process for a second time and here are some observations, going from 1.2.3 to 3.0 In unity 2017.3
1) Create Scene Variables is nowhere to be found in the Bolt preferences in 1.2.3
2) On step 10 Unity crashes immediately on start. It works if I try to start it again.
3) The Update Wizard shows no instructions, merely the status window where all I can click on is "close".
4) Trying to fix missing variables fails and gives an error message (which I lost because the internet ate my previous attempt at this post). I'll try to update another project and see if it happens again.
5) The colors are strangely dark, I had noticed this in past attempts at updating too.
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