I’m sorry, but I don’t really understand what you wanted to test…
walletB.dat and walletS.dat belong into the Nu application data folder.
Are the blockchain files (blkindex.dat, blk0001.dat) from the Nu application data directory as well?
Did you take them and copy them into the B&CExchange application data directory?
If so, please remove them from the bcexchange application data directory (you have backups of walletB.dat and walletS.dat, right? If not, macke backups, dump the private keys, do whatever is necessary
)
and start bcexchange 4.0.0 again.
If not, please explain what you did and maybe paste information from debug.log here.
Redact it in case there’s personal/confidential information in the output.