Just want to encourage you. The 2-1 nap transition has been one big struggle for us for 3 months! We're just about on the other side now, but we still have some awkward days/nights.
I agree with PP - I think you'll need to bring that nap up a bit - at least until you can get rid of those early wakings. Sounds like OT to me - both the struggling to go to sleep, and the waking up early. We had problems with only getting 1.5 hours out of him when he had 1 nap days too. It took about a week, and now he's sleeping 2-2.5 hours at his nap. I think what happened is his body gradually figured out that there was only going to be one nap, so he started sleeping longer! This apparently is common; lots of moms reassured me that the 1.5 hours would eventually stretch to 2-2.5. And it did! Once that happens, your bedtime will start working out better b/c she won't go so long.
Also, some of the women going thru this transition have found that after two 1 nap days, their LO needed a 2 nap day to catch up. Some find that doing it that way for a few weeks can help them get to the point where 1 nap days work out all the time.
So, try bringing that nap up by an hour, then also put to bed a little earlier. Even if she's not tired, worst case scenario she has a party in her crib. However, best case scenario is you get her in bed before she's OT. After a few days, you'll get a feel for what she can handle on this new sleeping schedule. When Owen was only taking one 1.5 hour nap, we did have to bring bedtime forward 30-60 minutes to help him thru. Sometimes it worked, sometimes it didn't (we had NW instead of EW), but gradually he was able to make the awake times on both sides of the nap.
Some of this you just have to endure. Obviously, monkey with the routine a bit to see if that helps. But truthfully, this is just an awkward transition. Sometimes they just need a little time to stretch to the new awake times they need to handle. This was the hardest sleep phase we've been thru yet! But, now that we're almost done, I can see how great it can be to only have 1 nap. Lots of freedom! So, keep the end in mind: it WILL come!