Did Sabran ever have any feelings towards Ros (or any of her other handmaidens [if that's the right word for them])?
No. Sabran lost her mother at a young age and has no living female relatives, so she always thought of her Ladies of the Bedchamber as family.
I would say that Ros has some buried feelings towards Sabran. She’d never act on or even acknowledge them, since she’s deeply in love with her companion, but in my mind, her love for Sabran is a complex thing and does tip slightly beyond the platonic. It’s also mixed up with her religious fealty to the House of Berethnet.
If you’re familiar with Christianity, you may know that the love between Christ and the church is sometimes described in erotic or marital terms, as in the Song of Solomon. That is, in my mind, something like how Roslain loves Sabran. It wouldn’t be a very healthy relationship, because Ros is devoted to Sabran in a way that sets the latter on a pedestal.