Prammanasudh, coming off a victory two weeks ago in the Fields Open in Hawaii, played 16 holes Sunday in the rain-delayed second round.
Francella didn't play Sunday after shooting her second straight 68 on Saturday to top the leaderboard at 8 under on the Bosque Real course, the longest on the tour at 6,932 yards and also the highest at about 8,000 feet above sea level.
'I'm still working on things. My swing doesn't feel completely perfect. I guess it never does,' Prammanasudh said. 'I'm just pleased to have played well today and hit some good shots to get some birdies out there.
'You have to try to play the golf course. There are some tricky holes out there and the elevation plays a big part in things and picking the right club is definitely the key.'
Play was delayed for 2 hours, 15 minutes during the afternoon, then suspended for the day because of lighting. Only 44 of the 74 players who made the 36-hole cut started the third round Sunday.
South Korea's Seon-Hwa Lee was 6 under, and Annika Sorenstam, the two-time defending champion making her first start of the year, was 5 under along with Karin Sjodin and Becky Morgan.
'I'm very happy where my game is,' Sorenstam said. 'When you get away from competition it's a little different. ... I try not to think too much about other things. I just have to focus on my game and hit one shot at a time.'
Mexican star Lorena Ochoa and Giulia Sergas were 4 under.
'I came here with determination to win the tournament,' Ochoa said. 'I feel very positive and happy and I have a lot of confidence in my shots.
Prammanasudh played in a group with Ochoa.
'It was a little crazy out there with all the photographers, media and all her fans,' Prammanasudh said. 'It's great to play around that. They're clapping for everybody and cheering everyone on, so it was just a wonderful atmosphere.'