I have added the microsoft date picker to a spreadsheet, and all works fine - but if I save/close the spreadsheet and reopen I just get a red cross where the date picker was. I have saved as macro enabled but every time it seems to disappear !
Not familiar at all ..
Have you tried fiddling with the security settings in Excel?
The program may be blocking it.
Tools/Options/Security .. and Macro settings (low or medium)