Please try the following 3 lines:
cd ~/Downloads
wget https://raw.githubusercontent.com/austin987/winetricks/dotnet462-noslim/src/winetricks
chmod +x winetricks
And then reinstall the bible application.
Please try the following 3 lines:
cd ~/Downloads
wget https://raw.githubusercontent.com/austin987/winetricks/dotnet462-noslim/src/winetricks
chmod +x winetricks
And then reinstall the bible application.
Thanks for your help @carmar! I really appreciate it! I ran the above in Terminal:
david@david-HP-Laptop-15s-fq1xxx:~$ cd ~/Downloads
david@david-HP-Laptop-15s-fq1xxx:~/Downloads$ wget https://raw.githubusercontent.com/austin987/winetricks/dotnet462-noslim/src/winetricks
--2021-03-18 13:55:17-- https://raw.githubusercontent.com/austin987/winetricks/dotnet462-noslim/src/winetricks
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 185.199.109.133, 185.199.108.133, 185.199.111.133, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|185.199.109.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 759999 (742K) [text/plain]
Saving to: 'winetricks.1’
winetricks.1 100%[===================>] 742.19K 3.11MB/s in 0.2s
2021-03-18 13:55:18 (3.11 MB/s) - 'winetricks.1’ saved [759999/759999]
david@david-HP-Laptop-15s-fq1xxx:~/Downloads$ chmod +x winetricks
david@david-HP-Laptop-15s-fq1xxx:~/Downloads$ ^C
david@david-HP-Laptop-15s-fq1xxx:~/Downloads$
I've then tried to reinstall Bible Study 6 Setup but it has STALLED during the installation again
Any more ideas??

Try:
cd ~/Downloads
sudo mv -v winetricks /usr/local/bin
cd ~/.cache/winetricks/dotnet462
wget https://www.dropbox.com/s/1bdocgbate8hc8z/dotNetFx462_Full_x86_x64_Slim.exe
env WINEPREFIX=$HOME/winedotnet462 /usr/local/bin/winetricks --unattended dotnet462 corefonts
Fingers crossed. This problem has been documented in 2018 and seems it hasn't been weeded out completely: Installation using wine gets stuck at .NET Framework 4.6.2 - WineHQ Forums
Wow - That ran for a good 5 mins @carmar
Unfortunately the result is still the same - the Setup Process stalls at Processing Microsoft .NET Framework 4.6.2

By the way, I took a photo of the Terminal screen when the program finished running, as it looked a bit strange to me. It ended with ... (deadbeef) stub.
The "FixMe's" are just for the WINE dev's. You can ignore those.
Are you installing .NET on Winetricks latest version?
Open Winetricks from your app menu as GUI and use it to delete all apps and data.
Then, try
winetricks -q dotnet462
Try what @Aravisian recommends and let us know.
Just as an aside, I also recommend looking at: Bible by Olive Tree Alternatives for Linux | AlternativeTo - Xiphos seems to be popular if you don't mind considering that. It can be installed by searching for xiphos in Synaptic. Sorry, I know this isn't helpful toward fixing the .NET problem but rather is an alternative, however, I don't know where to go from here.
Hi @Aravisian. I'm new to Linux so please be patient with me! I went to bottom left (apps menu?) and searched for Winetricks. I don't know how to open it as GUI. Please see the screenshots attached for the message on Winetricks. Can you please explain how I'd use Winetricks to delete all apps and data? Thanks.
Try winetricks --gui
Thanks for your help @carmar. I've run the above command and followed the prompts. Can you please confirm I should click OK to "delete all data and applications inside this Wineprefix"?
Correct.
Btw, when you install the Olive tree application, does it give you an option (checkbox?) to choose whether or not to install .NET? Some programs allow you to use a checkbox whether or not to install the .NET, although I'm guessing this one doesn't but I thought I'd ask.
Gtk-Message: 08:42:25.315: GtkDialog mapped without a transient parent. This is discouraged.
find: ‘/home/david/.local/share/applications/wine’: No such file or directory
david@david-HP-Laptop-15s-fq1xxx:~$
I've clicked OK and got the above dialogue in Terminal. I've then tried to reinstall Olive Tree Bible Study and it stalled at the same place again. I didn't get the option not to install .NET 
Thanks for all your efforts to help! I really appreciate it. I've got a lot of my own notes, highlighting and a few books I've paid for in Olive Tree, which syncs well between Windows 10 and my Android ph. I'll look at those alternatives you linked to, but it's not looking like Linux will be a good fit for me, which is such a pity 
I believe what Aravisian was asking was to do winetricks -q dotnet462 after removing everything (which you have now done) and then again trying the Olive Tree install. If you don't mind trying that one more time.
Thanks for picking up I missed that step @carmar.
I've run the above command and the installation was unsuccessful. It appears is the .Net Framework is corrupt. (see screenshots attached)
GUI = Graphical User Interface
CLI = Command Line Interface
When I suggest opening in GUI, this means to open it in your Familiar Graphical Window and when I suggest using CLI, this means to opena nd run an app in terminal. Running in CLI (terminal) means that the app does not have a Familiar Window with icons and checkboxes and entries - it is all Text In A Terminal. For example, when you run "sudo apt update", you are running the app APT (Advanced Package Tool) in CLI. It does not open a window with buttons on it.
Have you installed 32 bit architecture and support, first?
sudo dpkg --add-architecture i386
sudo apt install zorin-windows-app-support
sudo apt install winetricks
sudo winetricks --self-update
winetricks -q dotnet462
Thanks @Aravisian. Sorry, I'm really new to Linux, so could someone please give me step-by-step instructions on what to do as I'm not sure what to do next 
I am not sure what you mean- What I posted above is step by step. Which part confused you?
Sorry, the stuff about GUI confused me
I think I'm following what you're saying now!
I ran the above commands in the CLI, uninstalled the Bible Study app and tried to reinstall it, but got the 0x80070643 error.

david@david-HP-Laptop-15s-fq1xxx:~$ sudo dpkg --add-architecture i386
[sudo] password for david:
david@david-HP-Laptop-15s-fq1xxx:~$ sudo apt install zorin-windows-app-support
Reading package lists... Done
Building dependency tree
Reading state information... Done
zorin-windows-app-support is already the newest version (1.1).
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
david@david-HP-Laptop-15s-fq1xxx:~$ sudo apt install winetricks
Reading package lists... Done
Building dependency tree
Reading state information... Done
winetricks is already the newest version (0.0+20180217-1).
0 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.
david@david-HP-Laptop-15s-fq1xxx:~$ sudo winetricks --self-update
Executing cd /tmp/winetricks.Gz3c2IvP
Downloading https://raw.githubusercontent.com/Winetricks/winetricks/master/src/winetricks to /tmp/winetricks.Gz3c2IvP
--2021-03-19 14:30:11-- https://raw.githubusercontent.com/Winetricks/winetricks/master/src/winetricks
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 185.199.110.133, 185.199.111.133, 185.199.108.133, ...
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|185.199.110.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 880974 (860K) [text/plain]
Saving to: 'winetricks’
winetricks 100%[===================>] 860.33K 316KB/s in 2.7s
2021-03-19 14:30:15 (316 KB/s) - 'winetricks’ saved [880974/880974]
dotnet462 already installed, skipping
david@david-HP-Laptop-15s-fq1xxx:~$
You keep getting a warning about 64bit wine prefix. I do not know at all if this is related. But let's try to fix it and hope for the best.
In Terminal, paste in these:
WINEPREFIX=~/.wine wineboot
WINEPREFIX=~/.wine32 WINEARCH=win32 wineboot
WINEPREFIX=~/.wine32 WINEARCH=win32 your_32bit_executable.exe
WINEPREFIX=~/.wine WINEARCH=win64 your_64bit_executable.exe
I did a net search on Olive Tree and .NET installation and it appears you are not alone in getting that same error.
Oh, I see it also shows you are on an earlier version of wine. Why is that? It should be over 5.0.