I setup Win 7 on a separate partition. I can see the partition from Vista but I cannot see the Vista partition from Win 7 so I cannot access my files from the beta install. Any way of allowing access?

Go into disk management and assign a drive letter to the Vista partition.Ronnie Vernon has answered this with full instructions here Asrock K8NF6P, AMD64 3200+, 1.5GB RAM, Palit Geforce 8400GS 256MB, 500GB Maxtor SataII, Asus 1814BLT optical

Assign the next available drive letter to your Windows Vista partition. Afterwards, you will then be able to access your files on the Vista partition. Do be aware that the assignment of drive letters in Windows 7 has no affect at all on the other operating system's ability to boot. What I really, really recommend is you label your partitions in a consistent manner to what is stored on the partition. Drive/partition labels are persistent across installations in a multi-boot scenario. While booted into Vista, right-click your C: drive and assign the name Vista for your C: drive. While booted into Windows 7, assign the name Win7 to you present C: drive. Although the drive letters will change when you boot into your other operating systems, the labels are always there making it easy to identify one from the other. @