Hi Pipeline,
Thank you very much. I did carry on trying things out after my post and I successfully witnessed RB detect all the the ACID information. I'm not sure what happened previously when I tried this with the 2017 version. Perhaps doing it wrong, I wouldn't be surprised. But this is great and at least I can organise the the loops folders using subfolders. This is a brilliant feature.
There isn't much in the manual about the technicalities in the reference (either BB or RB). I need now to look at creating loops in RB and exporting them as ACIDized but I'm not sure that this works in the way I thought.. The last time I tried this the 'ACID' file just seemed to get auxiliary files added into the folder. But, brilliant as it is,

Thanks.