Cryptic 2505

[Glanrhos]

13a - action by those who won't stand for something? (3-2) s?t-?n sit-on?
17d - took steps about love with female - it's looking serious (2-5) p?-f???d po-faced?
18d - giving go-ahead for vote accepted by old ruler (7) o?????g
25a - e.g. Hilary Clinton, initially flexible (7) ????b?r
26a - Someting sweet returned, foe example? Surely not! (7) r?v?n?e

Thanks for some help and an explanation

[Dinkypuzzled]

13a. sit-in
17a yes paced (around o and f)
18d okaying
26a revenge (eg never backwards)

[Dinkypuzzled]

25a. climber (C + limber)

[Glanrhos]

Thanks for your help and explanation Dinkypuzzled it's appreciated.