SilverCreator v2.0b4 and later can now import most System 7 sounds into the new CAF format. Compressed sounds (such as IMA 4:1, MACE, etc.) will be decompressed and may become several times larger in size.
QuickTime Sounds are also converted. Standard MP3, MP4, etc. are converted to CAF without recompression and will remain the same size. Some really obscure QuickTime sounds may be decompressed. (If a QuickTime Sound fails to convert at all, it probably means you were doing something really stupid like importing WMA's with Flip4Mac. You are probably screwed.)
Please test opening any old game projects that you might have and make sure each sound plays correctly.
CAF stands for Core Audio Format which is the native format for macOS and it can hold almost any kind of audio compression format you can think of.
For Windows Game Compiling, all of your sounds are converted to uncompressed WAV. This really sucks: if you had a 4 MB MP3, now it's gonna be 48 MB. But we don't have QuickTime at all anymore (RIP QuickTime) and that's what we used on Windows. So all we have is "Crappy Windows Sound Playing Code that Bill Gates stole from whoever".
But I plan to look into this so that Windows games with a lot of sounds, don't need a fiber connection just to download...