Ok,
After leaving it overnight, I appear to be roughly where I want to be. I have a TOSEC folder which is based on the (TOSEC v2018-04-01) release and it's 134Gb in size. The issue must have been down to .zips inside of .zips, and yes NLS, it was from the PD torrent. I also decided I'd rather have it as just one level of zipping for the reasons you mentioned, that an emulator can read it like that, it is more as it was intended, and it won't cause any other hassles down the road.
The reason I wanted to go this way, apart from the hassles it can cause (as I found out) is that I wanted to have a crack at updating it myself, I have access to newgroups and stuff and maybe in the end, if I wasn't treading on anyone's feet (and once complete of course) I could maybe upload this version to PD. Of course if it is going to tread on peoples feet and/or upset anyone I won't bother, also as I'm still a stack of ROMs missing from a complete set, this possibility it still miles down the road, and also just an idea for now.
I do have another question about RV though, if you look at my attached screenshot, a lot of ROMs are in yellow, according to RV's key these are listed as "This ROM is missing here but has been found somewhere else, and so can be fixed", I've tried pressing "Fix ROMs" a few times, but nothing happens, how can I get RV to fix these?
Also, after trying a couple of times, I'm thinking there is no way to drag ROMs or folders of ROMs into RV for rebuilding "missing's" like you can with CMP? I'm thinking I would have to put any fixes I do get into the 'ToSort' folder and then press "Scan ROMs", "Find Fixes" and lastly "Fix ROMs" again?
Oh, also also, is there a way to get RV to remove the matched source files once rebuilt, like CMP does? ... Or does it do this anyway? I'm unsure? ... I extracted all the "zips inside zips" files, and that's what rebuilt my set to where it currently is, but the "ToSort" folder now has 1938 files in it that amount to 195Gb. These aren't part of the fully rebuilt set as I've moved that back into the original folder it came from, I'll just point RV to that folder in future instead of moving it around). Is it safe to delete these? Or are these files that we're unused in the rebuild? If so, there's an awful lot?
Anyway, thanks all for the help so far, I'm still not fully there, but I'm a damn sight closer than I was a few days ago. I now need to find a way to fill them "missing's", I will have a look through newsgroups, but other than that, does anyone have any suggestions of where I might be able to get them from? Other than waiting for a complete torrent, which of course has the potential to be not in this format again :\
Regards
Stef