When using the newest version of the Source Unpack, I for some reason can't do the Save Glitch. Instead I just fall through the ground into the portal after lining myself up. Is something setup wrong or what could be happening here?

i assume you're doing the 04 save glitch- try standing a little more to the right. you dont want to be directly on top of it but a little off to the side in either direction to get save glitch to work

Huh, it really was just that. Thanks for the help even though I was being dumb.