I'm now on my third PC in as many days (had to trade in my precious PS4 to get it ). Hopefully it will last more than a few hours (sod's law says it will pack up 61 days from now, just after my warranty ends).

Anyway, enough of the pessimism. I'm now on Windows 7, and would like to know what's the latest version of Quest that will run on W7, and if I download it, will it load the games I created on an older version of Quest (5.5.1)?

Windows 7 is supported, so the latest version of Quest runs fine on it.

Quest can always play games created for every previous version, and can always edit games created for the same major version (so you can edit your 5.5.1 game in the latest version).

Thank you.