I've been trying to use Installation Tool, yes. Is osm a different management tool? I was aware there was an older software (Device Manager?) for earlier versions of the phone system firmware, but didn't know there was anything later. I have Installation Tool v1.53c - if there's another piece of management software I need could you point me to where I can download it? I checked the SD card just now and there's no software installer on it in any of the subfolders. The SD card sticker says v4.95 while the system tells me it's running v5.01, so I assume anything additional was wiped when it was upgraded (but I'm guessing on this point).

Thanks for sticking with me on this!