Hi all,
I found that the new Plugin Registration Tool (from MSCRM SDK 6.1) removes existing plugin activities after the Assembly dll updated.
I am sure the tool will keep all my existing registered activities in MSCRM SDK 5.x version.
1. I have 3 plugin activities registered, e.g. Contact Post Create, Contact Post Update, Account Pre Create.
2. Then I updated my plugin dll (Account Pre Create) and upload in Plugin Registration Tool. I have to choose which activities to register (default all unselected)

3. As a result, two other plugin activities (Contact Create/Update) were removed.
4. It is very easy to remove all other registered activities by mistake because for some projects I have more than 20 plugin activities and workflows.

Anyone also has such issue and any resolution? Thanks.