it does not create or have any ability to modify tables (at least not since i last used it). it just allows you to view existing schemas through labkey. i think you have the option on enabling insert/update, but i have no idea how it would behave with a multi-key table. if you already have the tables, it's easy enough just to see what happens.

i've used this on our site when I had applications that needed a more portable solution and/or had other processes that interacted directly with the DB. it allowed us to get the UI provided by labkey while side-stepping some of the constraints and limitations labkey puts on you with lists.

for applications I viewed as longer-term I have generally created the schemas through a simple modules as matt suggested. i went this route b/c it was a little more structured, even more portable (labkey can auto-create the schemas), etc. it all depends on how you think you'd use this.