As you may know the “add to group” functionality is not currently implemented in the web client. There is a way to create a new ad-hoc group by selecting records from an existing group but no way to add records to an existing group (not to mention that the interface is a bit hard to use). In our case this was a crucial piece because the customer wanted to rely on the ability to add records to the “SyncSalesLogix” group to have them picked up by the Lotus Notes sync. Fortunately there is enough functionality in the API to build it ourselves. I created an “Add To Adhoc Group” smart part and uploaded it to the MSDN Code Gallery in case it is of interest to anyone else.

It should work with all entities for which the LookupView component works, though I only tested it with Accounts, Contacts and Opportunities. It is available as both source code and bundle-based installation and released under the open source Microsoft Public License (which is actually the only one available for MSDN Code Gallery).

One thing I should mention – it does not work very well for the Admin user. So make sure you test it out with a regular user.