Why Candles?

I'd like to know the answer to that, too. I noticed the electric radio and what seemed like a lit gas lamp in the parlor at the end. It could have been due to wartime blackouts, but I don't remember them mentioning it.

Throughout the film, they use oil lamps and candles exclusively at both Windwood and the grandfather's house. Scanning the scenes, I note candle lamps on the walls and even the chandelier over the spiral stair has candles. (Check/pause the scene when Rick is playing for Stella and she bolts.) I see no wall switches anywhere in the film. If you asked me, I'd say there's no electric or phone service in the house. I can't account for the radio(shown only once) other than a gaffe.

Contrast that with Miss Holloway's place. She's got two phones and what appears to be electric lights. Rick calls the Dr, but he's not shown speaking on the phone. There's no way to tell where he called from, possibly Stella's Dr's place.

Later, when they return from the first cliff episode, we see Rick's flashlight for the first time. He probably sprung for it after hearing the ghost sobbing his first night there. Maybe the radio is has batteries too? I never heard such devices were available.

I think the notion of wartime blackouts and rationing is a stretch. There's no mention or innuendo of it. In fact, every night scene I can remember, they make a point of showing curtain-free windows with the wind blowing trees and the sea raging in the background. You'll note Rick's studio is curtain free when they move in. Later, we see curtains hung presumably to control the sun rather than for blackout or privacy.
........
How about these?
1. The portrait of the mom was painted by the father. Stella clearly explains this. How is it, there are two identical portraits, one in stella's home(which we see when the dr visits her after the séance), and another in Dr Holloway's office.
2. What is the object on the grass in the scene where Stella bolts to the cliff (for the first time) while Rick is playing piano for her? It looks like a body. It never moves. It is never referred to or mentioned again.

Throughout the film, they use oil lamps and candles exclusively at both Windwood and the grandfather's house. Scanning the scenes, I note candle lamps on the walls and even the chandelier over the spiral stair has candles. (Check/pause the scene when Rick is playing for Stella and she bolts.) I see no wall switches anywhere in the film. If you asked me, I'd say there's no electric or phone service in the house. I can't account for the radio(shown only once) other than a gaffe.

Contrast that with Miss Holloway's place. She's got two phones(one is in-house and another outside line) and what appears to be electric lights. Miss Fitzgerald calls Dr H, but she's not shown speaking on the phone. There's no way to tell where she called from, possibly Stella's Dr's place. The three of them are shown walking out the study toward the front door of Windwood just before the call is placed to Dr H.

Later, when they return from the first cliff episode, we see Rick's flashlight for the first time. He probably sprung for it after hearing the ghost sobbing his first night there. Maybe the radio is has batteries too? I never heard such devices were available.

I think the notion of wartime blackouts and rationing is a stretch. There's no mention or innuendo of it. In fact, every night scene I can remember, they make a point of showing curtain-free windows with the wind blowing trees and the sea raging in the background. You'll note Rick's studio is curtain free when they move in. Later, we see curtains hung presumably to control the sun rather than for blackout or privacy.
........
How about these?
1. The portrait of the mom was painted by the father. Stella clearly explains this. How is it, there are two identical portraits, one in stella's home(which we see when the dr visits her after the séance), and another in Dr Holloway's office.
2. What is the object on the grass in the scene where Stella bolts to the cliff (for the first time) while Rick is playing piano for her? It looks like a body. It never moves. It is never referred to or mentioned again.

Anything relating to the war does not apply. The film was made in 1944, but it is set years earlier, starting on May 10, 1937, as the voice-over from Milland tells us at the beginning.

https://www.youtube.com/watch?v=03SwWWvCJsw

And there were battery-operated radios at the time:

http://www.radiolaguy.com/info/About%20battery%20radios.htm

http://www.farmcollector.com/equipment/farm-radios.aspx

I can't be more help than that, as I never really thought about whether the house had electricity or not.

Too busy smelling the mimosa, I guess.  (an angel, since we don't seem to have a ghost emoticon)

I don't know about the UK, but in the US it was still common in rural areas to have homes without electricity in the 1930s and '40s (film is set in 1937). Battery operated radios were available, though the batteries were expensive. Also remember, there was a passing reference to the age of the house being about 200 years old. Any electrical wiring would have to be retrofitted.

Nobody gets to be a cowboy forever.

I am very glad to see that some things have been archived from IMDb main site.

There were battery powered radios in 1937 (when the movie was set) and 1943 (when it was filmed).