It looks like Erel's batch file:
1) Delete's B4A's, B4I's and B4J's own historical backups before the main BACKUP.ZIP backup is performed so the resulting ZIP backup wont be too big.
2) Delete's all the \Objects directory because these directories only contain files that resulted from a compile operation and are not useful (because you can recreate them just by doing another compile.)
3) Since the RD is only used for the above two sub-directories, it should not delete any other files or directories (where your res files are)
But keep this in mind - you may want to remove the \AutoBackups lines from the batch file so it WILL preserve older versions of your files because Erel's batch file will not only delete those historical versions, but it will also erase the previous "Backup.ZIP" so when you do a new backup, it will delete the older one, so you won't have any older backups at all. (you could however, modify the script to remove the "del backup.zip" line and make it so the new ZIP backup filename includes the date text i.e "Backup-102719.ZIP" - this way your previous backups will be preserved when you do a new one)