It sounds like you are suffering from various environments behaving differently. One problem with Using OLE Excel data, the interfaces, to me that is, never seem to be very consistent. I've never been a fan of using OLE do try and present Excel data in my Drawings, actually I don't like OLE anything in my drawings. I have always been one to automate the process of back end data linking to actual text objects or even Tables in my drawings, then controlling the updates at either user request or via one of the AutoCAD API's. I know this is not much help, but you might want to consider some alternatives to OLE linking.
Good luck!
