In LO Base I'm having file corruption when saving over network, can anyone help?

I’m currently using LO Base 4.0.0.3 as that version seems to have the most stable report builder which is crucial for my print layouts. So far the bugs in all other versions, yes 4.1.1 as well, have all made it unusable for this database. I use many LibreOffice files, writer, calc, with no issue. Also other base files have no issue - only the most important one unfortunately, an Invoicing database.
What happens occasionally is when the file is accessed over the network upon saving it gets corrupted and can no longer be opened. When you try to open it it asks to filter it and when I try to uncompress the file or save it as a .zip it fails to do so, the file is completely corrupted. It so far has never happened with files other than the invoice database, and only when saving over the network. Using the file on a USB in the laptops works just fine, but is annoying.
We are currently using Ubuntu 12.04 on the main office desktop which is set up as a server for the other laptops that access the files. The other laptops are currently running Ubuntu 13.04 as the file server connections are retained and it seems to work better for networking. We had the same problem when using a 32bit and a 64 bit laptop that were using Ubuntu 12.04. We had the same problem when we were set up using the FTP? to browse the network before we had someone set up the main desktop as a server.
I have recreated the file several times – it seems to be somehow in that particular file that makes it prone to corruption. It is currently still being run as an embedded database, I am going to try to split it however to allow multi user access, because, I don’t know if this is related or not, but…
The file does not ask to be opened as a read only copy when it is already open and another person attempts to open it. It allows more than one person to open the file at one time, an embedded database not set up for multi-user access, and it causes the data from one person to be entirely lost while retaining only the other persons, invoices end up lost and over-written over.
Anyone have any ideas?