You see, 02R/20L is missing and therefore the STARs can´t be assigned to this runways. The logic in the sim is now, that all STARs will be disabled/suppressed.
You should use any 3rd party scenery which includes the missing runway and you will immediately see the terminal procedures. Our dataset still includes all terminal procedures.
Sorry, we can´t do anything for this … it´s the outdated scenery (and WSSS isn´t the only one, sorry to say).
Sorry, here the same with the Cloudsurf WSSS 3rd party scenery, which includes all runways (our package must be at the end of the context.xml file - but you don´t need anything else - you see that all the procedures are still included and that the sim suppress/disable the STARs due the outdated stock scenery):