I consider working with proxy to be really unecessary since PIV cpu (about 7 years ago!). DV editing is pretty sleek with current generation computers/hard disks. Even my old PIII laptop managed it some years ago. And Vegas always excelled at that.
So, why not just work with the stock footage and get rid of your timecode problems?
BTW, one of the Vegas major (and unique i think) advantages is the possibility to work with many instances opened at the same time. I always work like that myself with complex long form projects: as much instances as i need to visualise my footage easily (Vegas is so fast when opening a second instance), and copy/paste from that to a master. I vastly prefer this method to nesting. The only reason i use myself nesting is to reduce the number of tracks in a project (say, for a heavy compositing intro), or keep one editing source for a clip part used in many projects.
Hope this help (sorry for my so so english…).
Bastien