As you can see in the example file, I'm trying to settle the cloth on the floor to create some gathering and bunching, I'm new to Vellum so I'm sure I'm wiring this wrong because it's not working. Any pointers are greatly appreciated

The main issue you needed to fix was increasing the substeps and constraint iterations until the pops you saw went away. If you checked your scene, you could see that you were getting collisions, they just weren't accurate enough with the interpenetration you were getting. This was also due to how high res your cloth was. So, you had to increase the substeps and constraint iterations high enough to resolve that number of points. Uploaded the fix.

Thanks for the tip!