I figured out that rapid-uploader don't give an error message when you have uploaded a file that is banned, means a file that has been already uploaded to RS and then be deleted by RS due to violation of terms/copyright.
I also had problems with files that were almost 100MB in size (104890 kb). You can upload this files via browser but rapid-uploader says it's too big, but then you get an error.
Can it be that your IP-adress has changed during the upload process?
[edit]
i forgot to say: be careful with uploading-programs you can find in the net.
Don't give your acount info away too fast. Maybe try upoading some files as a free user to see if it's faster, and if, search the web to see if that program is related with phishing attempts.
_________________
> Amateurs | > Handjobs | JAV Movies