I think I have isolated the issue and should have picked up on it sooner tbh.
Not sure if you recall a while back I mentioned that I could not save to the TEnvDirectory dirInternalAppStorage using the jDownloadManager component but could to dirDownloads, dirNotifications etc., to cut a very long story short, I could save to Internal App Storage on 5.1.1 but not on 7.1.2 and can no longer save data directly to that location, but can save fine on 5.1, 4.4 etc. which sent me on a bit of a tangent.
The code below works perfect on 5.1.1, 4.4.2 but not on 7.1.2:
jListView1.Items.SaveToFile(GetEnvironmentDirectoryPath(dirSdCard)+GetInternalAppStoragePath+'/test.txt');
I did fresh installs back to LAMW rev. 691, rev.700 and used the latest rev.701 (0.8 version) but was still the same.
So to summarise, it's not a new issue and is to do with saving to the InternalAppStorage on certain Android versions, one being 7.1.2.