Using Lr for mobile off-line

Hello,

I have Lr for mobile on a Samsung tablet. I used it during an Alaska trip last year with a good deal of frustration. I don't think I accomplished download and sharing the same way twice during the 10 days. I will be traveling to remote Alaska again and will use the tablet and an OTG device to back up daily images from SD cards to a thumbdrive. I will shoot RAW+jpg for the trip and plan to save all to the thumbdrive and save jpgs I wish to share to the tablet's ext card. 

1. I would like to use Lr for mobile in the tablet (I use the CC photog plan) to view the downloaded images on the thumb drive or the tablet's ext card, to cull and to choose a few to edit/send. Is this possible to do without wifi or cell? (I do not use cloud services and I will not have a connection for this anyway. The tablet only works on wifi) I will send the finished photos to my phone, sign on to a Starlink connection, and send.

2. Can I create/store smart previews of the RAW images on my tablet to use for quick edits to share or is it necessary to use the jpg for this purpose? I see that there is a way to create smart previews (although who in the world would guess that a "!" would start a download for this?!?) Can I use this method to create smart previews? It looked as though I can't unless I use the cloud service.

3. Where can I find a workflow or an least an explanation for how to use the app and a key to decode the ambiguous icons?

Thanks in advance for any advice the community can offer to help me head off the frustration I experienced last year.

Janet