Hi. I have Lightroom 4 installed. I cannot download my CR2 files from the Canon 5D Mark III camera. I have downloaded Lightroom 5 thinking it was an update but it appears I have to pay for the program. Any ideas how I can get lightroom 4 to accept my CR2

I have Lightroom 4 installed. I cannot download my CR2 files from the Canon 5D Mark III camera. I have downloaded Lightroom 5 thinking it was an update but it appears I have to pay for the program. Any ideas how I can get lightroom 4 to accept my CR2 files ?