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Those are very good questions. The main difference between Enterprise Edition (EE) and Community Edition (CE) is that EE is updated less frequently as we wanted to provide the the best support and completely tested solutions. From the same reason there are some discrepancies between versions and activities. So answering:
- The best is to uninstall and install EE from .msi as this will install your Robot based on system thread instead of user, so you will be able to work with unattended robot as well.
- Yes you can, but remember that Orchestrator is also CE and it’s frequently updated. It might come to moment when your studio will not co-operate with Orchestrator properly.
- This I think has been answered in my entry
- It depends of how complicated project you have. If there is a version/functionality difference between some activities in EE and CE, then you will need to re-create this activities in EE from scratch. So it’s hard to calculate the time.