If you are creating or running an application and your list of export formats is incomplete, the problem is likely some missing dlls on the server/PC where the app is installed.  The list of export formats that you see is not typically controlled in the application code, but instead is determined by the list of dlls that the application finds at runtime.  Each export format has its own dll.  For example the one for text is U2Ftext.dll.  The one for Crystal Reports is U2Fcr.dll.  So if you find where these “U2F” files are stored you can see which are missing.  The complete list of files would be found on the PC that has your Crystal Reports designer.  I have CR2008 on a Win7 64 bit PC so my dlls are in this folder:

C:\Program Files (x86)\Business Objects\BusinessObjects Enterprise 12.0\win32_x86\

Adding the missing files into the same folder should complete your export format list.

If you are using the version of Crystal Reports that comes with Visual Studio 2005 you will only have  seven export formats available.  If you upgrade to the full developer version of CR, or to CR 2008, you have access to the entire list of export formats.