Attached you will find a small sample, implementing the described MultiSelect editor in Grid scenario. You will notice, that in Inline edit mode the Title of the MultiSelect column is correctly displayed. May I ask you to modify this sample, so it reproduces the problem observed and send it back to us? This way we will be able to troubleshoot that issue locally and to provide you with the most appropriate assistance for your case.
I am looking forward to hearing from you.
Telerik by Progress