I tried to @ Wilfried Rijsemus earlier on this community and it wasn't listed. Just two accounts with gray avatars appeared...
Ha, well I am here. I may have legacy accounts from trial groups. This is a known problem. see my post at our site as well. In short: Think like a Telligent developer :-)
Option 1: Use underscore
Option 2: Use lastname first
This is by design that I am not populated me thinks. I have disabled "Include in Search". I think the @ element uses the search to find people. I have opted to be only found via a conversation. If we are then Friends, I can be found via search hence @ mention
I will ask the admins to fix my accounts though