My company\'s main application is mostly written in C++ (with some Delphi code and components). We are upgrading from RAD Studio 2007 to 2010 for the next release, starting
You do not say what the data strings in your binary tuple format are for: is it necessary for them to store Unicode? When I transitioned from D2007 to D2009 I was able to keep some parts of the system ANSI-string only.
If storing Unicode is required, then you need to check if your existing data is compatible with a format such as UTF-8. If the range of values stored in existing data files present a problem, then I would make your next upgrade do a one-time conversion of any old data files, reading in the old AnsiString data and writing it back as UTF-8 to a different file name or extension, or by modifying appropriate file header data. I have been versioning data files for a long time, just to allow this sort of processing change.
I am only just starting a BCB2010 project, so cannot comment on your other questions, but I certainly had difficulty upgrading a Delphi project from D2007 to D2009 - though I was able to fix this by editing the project file, which is just XML.
Good luck with the conversion ;-)