If the database is secured, YOU have to unsecure it. WE will NOT break security for you.
There is no conversion to 64 bit per se. If you are using Windows API's in your VBA, you will have to convert them to be pointer safe. You can also use conditional compliation so that the API's will work in either environment. Someone can point to a link of a bunch of common APIs so you can see what needs to be changed. Otherwise there is no "conversion", internally, the .accdb doesn't need to change. An .accdb with NO Windows APIs can run using 32 bit or 64 bit Access with no problem. It is only .accde's where you will run into a problem. If you distribute an .acccde FE, you need to compile in 32 bit Access if you want to run it with 32 bit Access and you have to compile it with 64 bit Access if you want to run it with 64 bid Access.