To answer your questions- There is no temple in JA. There will be one day, but the church is going to need to do some growing first. Jamaica has about 5,000 members, many of which are less active or inactive. That being said, there are also many fantastic strong members here that make up the backbone of the church. The church is growing here, and still has a long way to go, but it has been cool to see all of the changes that have taken place over the past two years. Jamaica now has its first stake.
The nearest temples are in Panama and the Dominican Republic. The church has a program that allows members that need to go for their first time to go for next to nothing. Temple trips happen semi-annually. It has been cool to see people go to the temple and come back, just full of light. I love the people here. They are incredible.
As for new members being retained in church, it depends on the person, but I think we do pretty good with retention nowadays.