How_Do_I,
The reason your open parenthesis R close parenthesis is changing to ® is due to the Options page of the Excel workbook. To stop the conversion goto File-> Options -> Proofing -> Auto Correct Options… ( a button in the upper part of the Proofing window). There are two ways to deal with the issue. The first is to uncheck the Replace text as you type check box. This will stop all text conversion. The second option is to just delete the (r) to ® conversion. This will leave all the other conversions intact
HTH,
Computerman