I was just scrolling back through the posts and saw your post for the first time and that no one had addressed your concerns. I must have missed it myself since I usually like to offer ideas that have helped me. I, too, took ownership of a pop-up this past December (and had one 20 years ago for a couple years) and have tried to read up on tips on the forum here. Here's my try at your two questions...
On the first one, it's important to make sure everything works. You'd hate to wake up to a smoldering heap because the electrical devices were tried and true. Read post #17 on this thread
Everything worked but not when it should have while in a closed position. I think to answer your question, yes you can plug it in, just make sure heat generating devices are off or properly ventilated.
I run my fridge on propane a day or two before a departure while it sits in my driveway, whether the camper is open or closed. It seems to run the coldest on gas verses AC or DC. I also run it on propane while traveling down the road BUT the crowd here on the forum is split on that one. I am very comfortable with my decision though. I was a fire investigator for eight years with the state police where I live. I learned a lot about propane and respect for it during that time. I can also tell you I never investigated a "traveling camper fire" in all those years. It's a mixed bag though and if others begin to chime in here or you search the forum, you'll see.
Oh, welcome aboard too! [emoji4]
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