There is also the autosave feature.

Once you save a scene, this will save backups periodically. Then if a scene gets corrupt or crashes, you don't lose everything

If you're having trouble with a product, it's better to contact support https://support.renderosity.com/ than to post in the forum. You'll have a better chance of it getting fixed.

The reason why Daz moved from 1 figure to male and female was content creators were having trouble creating something for the combined. I forget what the issue was, but I think it was textures, but I've slept since then so I may have forgotten.

In addition to adjusting render settings, you may need to adapt your materials.

I'm not sure which figure this is but his face shader is a lot less shiny than the back of his head or his arm.

The bump map on the table and chairs seems a little strong.

And your lighting seems to need work. I don't see any shadows. Make sure you don't have too many lights and make sure at least one light has it's shadows turned on.

Here is my test render render settings

This is my intermediary settings. This is sometimes my final image settings but I usually need to use the denoiser in postfx so if I try that and I lose detail, I'll go to the next settings.

This is my final settings. I don't usually go higher than this.

Sometimes I leave the Adaptive Sampling checked, sometimes I'll turn it off. It depends on if the scene looks grainy with it on and if I want to use the denoiser or not.

You can lock things, but it may be a bit tedious. Under the object menu, there is a lock object option. The problem is that you must lock every body part for every figure and every prop individually. There is no option to lock them all at once.

You are likely moving the items as you select them. It's easy to do if you're not careful, especially if you don't have a steady mouse hand. If that's the case, I recommend using the hierarchy menu to select your items.

I’m away from my computer so I may not be exact. To help with the wall, if it is a separate piece from the rest of the house you can either hide it or uncheck visible in camera. Both are on the properties tab. If it’s all one piece, there is a work around that’s too complicated for me to explain from memory. 

It’s likely a one sided piece  of you go into render settings and click on the preview tab there’s an option for showing or hiding back facing. I don’t remember the exact wording. Set that to show back facing. Then you won’t have hidden walls anymore. 

It’s hard to advise for the render settings when I’m on my phone. Under load presets try one of the higher quality options. Low quality is good for test renders and higher ones are good for final images because they take longer. 

I've never seen something like this before. I think hborre's questions would be a good starting point. Once we see that, we might be able to come up with other ideas

Congratulations to all. Lots of great work here

Check with https://support.posersoftware.com/

There were a number of spam posts removed this morning. You may have been seeing a result of that

Dawn is a figure created by Hivewire who used to have a store on their own site. They now sell here. A basic version came with Poser. You can find the full version of Dawn here https://www.renderosity.com/marketplace/products/146732/dawn-special-edition. Things that are compatible with her mention they are compatible.

Make sure you check the software compatibility because she's compatible with both Poser and Daz, but not all of her clothing is.

render reward points for vendors is for members who have stores here.

I've never done much with the shortcuts so I can't say much. The only thing I can think of where this happens when you restart is what are your launch behavior settings. I'm assuming you don't have it set to factory default but if you have it as the preferred state, did you remember to save the preferred state after you set all your shortcuts?

I have a Ryzen 7 and both 12 and 13 work fine. I use my RTX 2060 for rendering whenever I can though. It's so much faster. I'm sure either of your will be even faster if you use superfly.