Hi Anna
I investigated your site now a little and found following:
It seems you are mixed up a little by the different ways, how an OpenSim account can be created via jOpenSim:
The first link "Login / Register" on your website goes to "index.php?option=com_opensim&view=inworld&layout=default.create". This is for creating an OpenSim account for
already existing Joomla users and should be visible for registered users only. Once a user is registered and logged in in Joomla, there is written the email just as text for the initial OpenSim account creating procedure regardless of the settings in jOpenSim (I admit this is a bit confusing).
After the OpenSim account is created, the page will then display the edit form with all fields enabled from jOpenSim settings.
If you want new users create a Joomla account AND an OpenSim account in one go, the plugin jOpenSimRegister is the one. It is installed with you and it looks as if it
does have problems with this template. When you change the template e.g. to Beez5 and look to your "index.php?option=com_users&view=registration", you will see the Firstname and Lastname fields turning up between "User Registration" and "User Profile". But it does not with your desired template
During developing another commercial plugin lately, I have found some nice and interesting new functions in Joomla 2.5.x and will try them out soon with jOpenSimRegister in hope that this will solve this issue.
Also: I could see that you already have some existing OpenSim accounts, but no Joomla account for it. To let those users benefit from the features of jOpenSim, you need to create a Joomla account for them (or let them create it) and "connect" the Joomla account with the OpenSim one via jOpenSim User management with the "Joomla <--> OpenSim" button up right. Alternatively (e.g. if they are too many to do so manually) you can enable the "Inworld Account Identification" in jOpenSim settings to provide some inworld terminals, where existing can connect their OpenSim account right themselve in your grid.
I hope this could clear the registration procedure a bit
Greetz
FoTo50