Hi All. In short - when I crop a clip in FCP 10.1.3, the clip renders and then the entire thing turns to green frames thus making it useless and requiring me to find that clip again and plug it back into the timeline. Any ideas on how to prevent this? I've already deleted "Event Generated Render Files" and it still happens. Here are some details that may shed some insight into the situation: Codecs: H.264, Linear PCM Resolution: 4K Editing in proxy - actual file is on an external - my early MBP can't handle the 4K files. Camera: Sony AX100 4K Any ideas? I can't get this project done because this has proven to be the major roadblock. Thanks in advance for reading and any responses.