Not that I should be picky, one should be developer to install the OS. You don't seem one.
Also, it's common sense to keep a TM backup.
What you should do is to partition the drive and install Snow Leopard again.
And simply copy the Applications and paste them into the your /Applications/ directory under the snow leopard partitions. And transfer other files in the same way. :|
If u install this in your computer like I did,Can you eventually get other updates and final release of Lion,Im not planning to go back to SL