Reloading questions?

[PA BEN]

Went to Cabela's yesterday and purchased a Lee Anniversary Reloading Kit and a vibratory case tumbler. The instructions are vague on most stuff, so I have a few questions. I"m new at this so bare with me.
1. How many times can you use the media?
2. It came with a bottle of polish. Is this necessary? Does it ruin your media?
3. Also, the inside of some of my case's are green, I shot these in snow or rain and the insides are not that clean. Will the tumbler take care of this? Is is something I need to be concerned with?
4. As far as dies. Adjustments are very vague also. I'm starting with 45 ACP, I see in the reloading book that each load has a different length to the finished round. Please help with this adjustment.

[Buckblaster]

Your case tumbler will work best if you put some polish in with the media. The media will last for years depending on how much you use it. Just change it when the cases aren't coming clean as quickly anymore and the media looks black. The green cases should come clean when polished. Polish your cases before resizing so primer pockets get pushed clean when punching out the primer during resizing. One thing to watch for is when you are getting ready to resize, check the clean cases for splits or abnormalities. They are much easier to spot when clean. As for other questions, you might look at their website, http://www.leeprecision.com/html/instruct/index.html .