"does motion run in 10.3.4 ?"
Sorry, the answer is
NO.
Don't know the reason behind it, but I saw the installer does check the OS version on the VolumeCheck script.
//-----------
...
if(CheckVersion("$SYSTEM_VERS", "10.3.5", "ProductVersion", "<"
) {
$badOS = 1;
...
//-----------
Antonio Hui