I am currently running FCP 7 and have been asked to do some editing work for a friend who uses FCP 6. I feel that the files from 6 will be transferable to seven, but once altered in seven they cannot be re-opened in 6. What can I do in order to circumvent this issue? Is there any way to open a file from 7 in 6? Should I just attempt to install 6 on my computer, and if so, will it disrupt the use of 7?