Steps to reproduce:

1. Imagine you are an author of loadable module.
2. Your users can build your module simply by running make.
3. You want to make installation process as easy as make install.

Result:
This is impossible. According to documentation:

The modules must be located in directory specified by LoadModulePath.

It is not an option to install module to the default LoadModulePath because it will deny user ability to change it. Module can't also choose it's own LoadModulePath because it will lead to conflicts between different modules.

Expected:
Allow to specify absolute path to module in LoadModule, this way module's installer will be able to point Zabbix to the correct place without messing up the rest of configuration.