I've downloaded the undelete_1.4-2_mipsel.opb and undelete_1.4-2_mipsel.opk files but cannot find any instructions on how they are loaded. However, I have yet to find the instructions on how to install these packages?
No problem. The package will have been installed with some default values for the number of days that things are kept in the bin and the name of the bin - you can adjust both of those through the Settings page in the web interface. They will take effect after the Humax is next put into full standby (amber ring and click as disk turns off).