I am at a dead end an I could really use some help.

I intern for a huge company. My projects involves creating an application to automate/simplify the work of a retiring employee. 

The problem here lies in the strict company policies. I am a developer stuck at business end of the company. Therefor IT gives me nothing:

1. I don't have a server (nor web nor database)
2. I can't create a server, because no pc will be running and we can't keep them logged in due to single sign on with company cards.
3. I can't install anything on the pc's in the network.
4. I can access a share file server, that is backed up every day.
5. The libraries involved have to be free
6. A central database has to be accessed by a dozen of users (at once)
7. The database will recieve new data every day and will grow accordingly
8. The users will both read and write from/to the database
9. Preferably C#.NET or WPF solution
10. Application needs to open files stored on the shared drive. ( Only once, the important information will be extracted and stored in the database.. the file will then be removed)

My initial idea was to use silverlight (which runs standalone) in combination with SQLite. I ran a test and Silverlight files stored on the shared drive work. (Silverlight is installed on every pc on the network) This is my preferred front end. However (correct me if i'm wrong) I tried SQLite-net and I needed to add the sqlite3.dll to my windows/system32 folder, but on the network PC's I don't have access to the Windows folder, so this can not be done.

Also I read that SQLite or files in general can become corrupt when accessed by multiple users as one, so maybe I thought locking was an idea.

Which solutions are there to my problem?