For your renaming job, look at
MultiRen or
SRename from Aminet.
For reading Joliet CDs, you could use something like
this from Aminet, or use a CDROM filesystem which supports the reading of Joliet discs, such as CacheCDFS which you can
buy or it comes as standard as part of OS3.5/3.9.
As for the file errors in the archive, check you're using the
current LhA version. It also could be another issue such as the hard disk file system set with a MaxTransfer value which is causing problems. Use HDToolBox to try a lower value such as 0x1FE00. Careful with what you mess with in HDToolBox as you may accidentally erase the disk contents.
