As for your chord entry 'problem' that hasn't been addressed yet, I think that is pretty much how it works in BIAB, although instead of hitting 'Enter' after typing a chord letter you can also just click the next bar where you want to place a chord and the previous one will show up then as well. It is somewhat different than a word processor in that regard.
If you are comfortable with computer troubleshooting and getting into the guts of the thing, you might try swapping in and out some of the memory modules, i.e. go down to 2gb and try it, and if it still has a problem, swap out the 2gb in the system with the other 2gb modules you removed, and mix and match them from there to see if you have a bad module. I doubt it is hardware related, but worth a try. Since your RT disk is not working it is possible that the song you are trying to create is asking for one of those RT's and the file is corrupt and killing the process.
Try some other RT's that you know are good and see if it still does the same thing. Finally, make a new song and redo the whole thing. Perhaps the original has been corrupted in some way.
Good luck.