I don’t seem to have a problem with this.
Where are you deleting the Time Entries from?
If you are doing it from the Project View I have found that the time entries remains on screen but they ARE deleted from the view when you close and reopen the project view.
If that is not the case can you please clarify if you are drag and dropping from the week view or project view or some where else?
(I am running Win Vista 32-bit so if it is an OS issue, I can’t check that.)