I don't believe there is a Mac app to load applications. Try PocketMac
It's buggy, not very intuitive and the there is no bluetooth sync that I am aware of.
FYI: I have never used Missing Sync, and typically I do any syncing/loading from my work laptop that has XP. It is my only regret switching from PC to Mac is the lack of Blackberry support/products.
Make sure you are using a powered USB port. If you are trying to connect via a hub or the ports on the Mac keyboard you will have problems.