Classic Yes and No.
You can open it. You can edit it. Will it break something?
Maybe.
Here's how. Safest to compile a CHM first even if you don't
want it. Update the HHP file. Trash the CPD and XPJ files and use
the HHP to open the project in X5.
In the topic on Opening Projects on my site, I set out what
gets lost and how it is easily recreated. I don't know about
variables that got introduced in RH6.
Maybe if you are not editing too many topics, you could just
replace those files in your colleagues copy using Windows Explorer?
Backups everywhere!
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