More to read
I think a good starting point can maybe this [Tutorial] Forms in OpenOffice.org Base. You can find there also links to other tutorials. Not all tutorials are even important for you
Are you running an embedded database (the default setup) or a split database? If a split database, which back-end are you using (HSQL version ??, MySQL, etc.)?
Are the pictures embedded in your database or linked to outside files?
Databases are designed to handle very large amounts of information, so too much information is not the problem. It sounds like a bug of some kind, and having more details about your setup might help the community identify what is triggering the bug, or possible workarounds.
OpenOffice 4.1.1 on Windows 10, HSQLDB 1.8 split database