I thought he would get her in an endless loop of portals falling from one to the next back to the first and so on until she surrendered.

Cisco vs Gypsy
When Cisco shot Gypsy she fell down but it seemed like she was unable to get away meaning Cisco needed to show mercy so she can live. Gypsy did the same thing to Kid Flash when she trapped him while he tried to run, if she wanted she could have killed him but decided to show mercy.
Barry as well was handcuffed by her so when Cisco had her she knew there was no getting away. That's why she accepted defeat.
Cisco could have decided to trap her from the moment she tried to open portal dimension but since he was attracted to her he decided to get kicked a little, remember Cisco went there knowing exactly what and when to do in order to win.

And DC will probably adapt this new version of Gypsy into the Rebirth comics. I hope they do. I am old enough to remember when the character, Gypsy was first introduced in JLA comics in the mid 80's (a barefoot, teenage runaway thief/con artist with invisibility powers). A non-gypsy white girl who likes to dress up like a stereotypical gypsy, she was introduced along with that other walking, talking stereotype, Vibe (break dancin', grafitti bombin', Latino gang member from El Barrio, always substituting the word, "chu" for "you" when speaking). This new version of Gypsy looks actually coollike new Vibe.
.
When I'm good, I'm GOOD. When I'm bad, I'm BETTER.

I don't actually see how Cisco "won". He knocked her down once, after she throttled him on his ass and into the ground 4 or 5 times. The whole ritual of her conceding HR after the loss was nauseatingly hokey, but I guess it was supposed to just be mildly amusing, which I guess it was.

Yeah, well she's really hot, so it was good episode.
WE GOT MOVIE SIIIIIGN!

Well if you find the enemy's weakness then it's just to exploit that weakness.

It was