System Manager 2.2 requires 64bit JRE if your OS is 64bit. The following is info from the System Requirements :
32-bit or 64-bit Oracle Java Runtime Environment (JRE) 7
• Installing 32-bit or 64-bit JRE depends on the operating system. If you have a 32-bit Windows
or Linux operating system, 32-bit JRE must be installed. Similarly, if you have a 64-bit
Windows or Linux operating system, 64-bit JRE must be installed.