1. The green/black stills issue is a known issue with version 1.5 Premiere Pro 2.0 eliminates this issue. However, if you reduce the dimensions of the stills, it will no longer be a problem in 1.5.
2. If you have Premiere Pro 2.0, I would install it. Remember, it doesn’t install it over 1.5, so you can have both 1.5 as well as 2.0 installed on the same system. However, before you open your project in 2.0, make a copy of it, just in case.