Hi,
Fred schrieb:
We are building a sort of panel of participants who will participate in multiple surveys.
The LimeSurvey Sync Drupal module provides many features you request :
Fred schrieb:
The surveys we want to keep each participant's information confidential and make it easy for them to see their survey "workflow," surveys they started and didn't yet finish, and surveys they previously submitted.
--> Handled by the LimeSurvey Sync Drupal module
Fred schrieb:
including new invitations,
Not done but easy to create.
Fred schrieb:
We would maintain our own tables of user accounts and survey history
--> Handled by the LimeSurvey Sync Drupal module
Fred schrieb:
build a small portal for panel participants to enter through.
--> Here is a link explaining
how sending a survey invitation to a subset of your registered drupal users
Fred schrieb:
When a user logs into our system and elects to begin a survey a token would be issued through our application and written to the Limesurvey database. These tokens would have a short lifetime, so if the user needed to access the survey again later, they would return to our portal and be issued a new token and directed to the survey. The survey itself could be enclosed in an iframe
.
--> Handled by the LimeSurvey Sync Drupal module
short lifetime --> 2hours by default.
survey itself could be enclosed in an iframe --> invisible iframe or a lighbox.
If the user edit its respond a new token is generated, and a copy of its previous answer is keeped (This is a new feature that not exists into LimeSurvey !). The submissions history is enhanced.
Fred schrieb:
It's possible we would start with something like Drupal or Wordpress or another CMS
Drupal is very secure.
Fred schrieb:
1) Has anybody done this before?
.--> me !
You can easily try out this module on the demosite ! 
