changing the default settings

This is possible if you create a startup script for your Integrity Client.

For your example on UNIX, you would want to set the MKS_IC_PROPERTIES and MKS_IC_INSTANCE_DIR environment properties to /var/tmp.

MKS_IC_PROPERTIES=/var/tmp
export MKS_IC_PROPERTIES
MKS_IC_INSTANCE_DIR=/var/tmp
export MKS_IC_INSTANCE_DIR

I have included a sample batch script for Windows below:

@ECHO OFF
title "10.7 Client"

:: Set the PATH variable to the Integrity Client's bin directory
set PATH=C:\Program Files (x86)\Integrity\IntegrityClient10_7\bin;%PATH%

:: Set the variable for this client's preferences file
set MKS_IC_PROPERTIES=C:\Program Files (x86)\Integrity\IntegrityClient10_7\PersonalSettings\IntegrityClient.rc

:: Set the variable for this client's viewsets, sandbox registry
set MKS_IC_INSTANCE_DIR=C:\Program Files (x86)\Integrity\IntegrityClient10_7\PersonalSettings\

:: Switch to this client's bin directory to ensure we run commands from this context
cd C:\Program Files (x86)\Integrity\IntegrityClient10_7\bin

:: Start the client process
im gui