What is the impact when the "Specify Application Server Home" is set to during APM Agent install, or if the path for the instrumented application server changes after the initial APM install?
Basically the purpose of specify application server home is to "Specify the home directory of the application server to monitor. The installer will use this information to determine suitable files and settings for your system. If unsure what to put, or if the application server is located on another host, press Enter to accept the default."
What this means to the installer is that it will pick up any zip or jar files in that directory you specify and extract them to the Agent's wily/ directory. This is for use by the Agent to pick up any additional files that it would need for the application you are monitoring.