1. A few hours should be fine without any special padding.
2. I currently have three, with a fourth on her way. Two lie on their backs in my bed whilst the third stands, as will the fourth. After two weeks the standing one will move to the bed and one of the lazy ones will stand. Mine lie on their backs for months, occasionally being moved for “recreational activity” and photo shoots.
I have yet to have any problems with compressed TPE. Leaving them lying on their backs is one of the recommendations for long-term storage provided.
With proper standing feet, she should be able to remain standing for a reasonable length of time. Never leave her free-standing. Lean her back against a wall or a cupboard with a memory pillow or something between her and the wall. Put socks and trainers on her feet to protect them.
Do not leave her in a sitting position for too long as this will crease the TPE at the top of her thighs. The creases should eventually disappear when you straighten her, but best to avoid them in the first place.
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