So I think I figured out how to do this. Using the code by pilotdrh2003, found here: https://www.mobileread.com/forums/sho...postcount=1210
, thanks to WS64, I altered it a small bit (so it goes to the appropriate directory on firmware 3.3 (uncomment the 3.X and comment the 3.3 section if required). Here, there are Launchpad shortcuts you can use to do it. Easy peasy.
Please test to verify that it works. FYI, one other customization is that it is set on the 'us' directory. So change if needed.
The fix is already included above, in the first post. Note: if you have a /mnt/us/screensaver-timeout file with a custom screensaver timeout (in seconds), it will override whatever Launchpad shortcut time you use when you run one of the shortcuts.